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Why Is Your Card Machine Not Working: Issues and Solutions

Payment Solutions
Running a Business

Why Is Your Card Machine Not Working: Issues and Solutions

Published date: 31.07.2025

As a small business owner, you work hard to ensure a smooth and consistent flow of sales. And your trusty card machine is your best friend in ensuring you catch all possible sales from different card payments, apart from cash.

But whether due to a technical issue or some other fault, you’ll sometimes experience your card machine not working. This can really put a spanner in the works for your revenue flows and that’s why you’ll want to take quick measures to reduce the impact of your card reader malfunctioning when you need it most.

To help you with this scenario, we’ve prepared the guide to help you troubleshoot various card reader problems. This will allow you to continue accepting multiple forms of payment while providing a smooth customer experience. Let’s begin.

Introduction: Card Machine Downtime and Its Impact

Every merchant that uses a card machine at their business wants seamless payment processing. However, just like any form of hardware, things can go wrong and often at the most inappropriate time.

Let’s explore the impact of card machine downtime in more detail in what follows.

The cost of a non-working card machine

We don’t have to spell out the obvious: a non-working card machine can mean serious loss of revenue for your business. This is especially valid with a growing number of consumers preferring card payments over cash.

Other possible impacts include lost sales, customer frustration and, unfortunately, reputational damage and risk for your UK business.

Several key figures highlight card machine downtime across different UK industries:

Retail and hospitality: SMEs face an average of more than five major payment‑system outages per year, with each outage lasting approximately 84 minutes on average. The cost adds up to around £1.6 billion per year.
Bakeries/food and beverage: Even a 2–3‑hour disruption can mean hundreds of pounds in lost revenue.
Personal services/barbershops: With a typical service costing around £15 to £20, even a one‑hour outage could disrupt multiple appointments, complicate reconciliation, and frustrate customers. Lower footfall during outages means lost revenue per hour is hard to recover later.
Other SMEs: Tech failures, including card machine failures, cost an average of £3,100 per SME annually.

Common scenarios when card machines fail

Regardless of whether you use an in-store terminal, a mobile or portable card reader, card machines can fail for several reasons. These include connectivity issues, power failures, payment processor downtime or card reader malfunctions.

It doesn’t matter if you use your card reader at ad hoc events, such as pop-up stores, or in hospitality settings, the bottom line is that a failing card reader can impact your sales and business.

The importance of quick troubleshooting

Recent research shows that as of 2025, the cost of payment system failures to the UK retail and hospitality businesses is roaring at about £1.6 billion annually. While the average tolerance of users to payment disruptions is around 6 minutes, less than 30% of them ever carry any cash when shopping.

The result is immediate revenue loss.

Lost sales add up quickly, and slow response to issues can harm your business reputation. Breaking the customer journey is very likely to send your customers right to your competitors across the street. And while financial loss is bad, what’s worse is the worsened long-term customer trust and the loss of hard-built customer loyalty.

In small service-oriented teams, prolonged payment disruption also causes frustration in the staff itself. Quoting a real-life UK-based IT business, downtime can lead to “a stressed-out team, poor morale, and even burnout”.

What Are The Most Common Card Machine Issues

Your payment terminal is a vital part of your business. But when it fails, operations can grind to a halt. To stay prepared, learn about common problems and how to solve them.

Below are a few examples of issues you might encounter.

Connectivity problems

Most modern card machines operate through Wi-Fi or mobile data. Sometimes, they also operate via a Bluetooth connection. Whichever is the case for your card reader, interruptions in your internet connection are potential issues you should be prepared for.

Other connectivity problems include SIM card issues or something as small as weak signal strength.

Payment declined errors

If you are seeing “payment declined” errors, it may be that your card machine does not support contactless payments. The solution here is to simply switch to a Chip & PIN or magnetic stripe payment.

However, the possible cause could also be due to the card your customer presents. Possible card issues you could encounter on the customer side include that they’ve reached their daily spending limit or that their card has expired. In these cases, the fault lies with the customer and not necessarily your card reader.

For example, a few payment error codes you could see on your device include:

Error 05/57/62: You may wish to suggest that customers check with their bank to enable them to perform specific transactions.
Error 14/55/54: Here, the signal indicates that you will need to add input validation and expiry checks on card forms.
Error 91/96: Retry logic kicks in, which essentially asks to try again later. This is often a helpful path to take.
Error 51/65: We recommend that you politely suggest an alternative card or payment method to your customer.

Bear in mind that every PSP’s card machines differ, and error codes will be dependent on the machine in question.

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Software or firmware errors

You may encounter software or firmware errors when processing payments. One common issue is outdated software, which can cause the screen to freeze or become unresponsive. This often happens when the application fails to load due to a corrupted update or an interrupted startup.

Furthermore, you could experience:

Transaction timeouts;
Missing configurations;
Missing EMV parameters;
Communication errors with the host;
A looping/rebooting message;
The card reader may not be detected on the device.

Payment apps can also malfunction, preventing you from accepting payments.

Hardware malfunctions

The physical machine itself could also be a cause for a non-responsive or malfunctioning point-of-sale (POS) terminal.

For example, the card slot may fail to read the cards, the touchscreen may be unresponsive, and your printer may fail to work and therefore issue receipts.

Power or battery failure

The power and battery life of your payment device are especially relevant in hospitality settings like restaurants and coffee shops, where staff bring the card reader to the customer’s table.

In these cases, the device often isn’t connected to a power source or charging dock during use. This can result in dead POS terminal batteries or the charger could be faulty, resulting in the terminal shutting off unexpectedly.

With a myPOS card machine, you’ll always be able to enjoy a long-lasting battery for a full day of accepting payments. Additionally, charging your device is fast and convenient with a type C cable.

Terminal not registering payments

Last but not least, your terminal may fail to register payments at all. This is the case that’s typically usual for older devices. It manifests as issues with tap or Chip & PIN detection.

It could really affect your payment acceptance. You’ll be stuck wondering if a payment has actually gone through into your account or whether you need to run the customer’s card through your terminal again. This can result in a double-charge for the customer and cause an unpleasant situation for them.

Step-by-Step Card Machine Troubleshooting for UK Merchants

Now that you’ve seen the common issues with card machines, you need to know the key troubleshooting steps to try before contacting your merchant service provider for deeper levels of customer support.

These steps include the following:

Restart the card machine: Sometimes, a simple reboot helps restart the operating system. Such a hard reset often resolves most temporary glitches.
Check the network status: Test the Wi-Fi/mobile signal, switch networks, reset routers or check the device’s SIM settings.
Ensure the card machine software is up to date: Double-check the machine’s manual on running software updates manually or enabling automatic updates.
Inspect the hardware: Check for hardware damage such as dirt in the card slot. Look for signs of physical damage or loose charger connections.
Confirm your merchant account and payment settings: Ensure the device is linked to the correct merchant account and acquirer.
Try a test transaction: Use a personal card or low-value item to verify functionality.

Taking these measures will help you get back up and running in no time.

When to Contact Support

Even with proper maintenance, there may be times when you need to contact your provider for support.

Here’s when you should do so:

Persistent errors or system crashes: If the terminal freezes regularly or fails across all payment methods.
Failed settlement or batch uploads: When transactions aren’t uploading to your account or being processed.

If you have a myPOS card machine, rest assured that you can reach our customer support through phone, chat, and UK-based technical assistance. With myPOS, you’ll always have a friendly and knowledgeable member of our team ready to assist you.

How To Prevent Future Card Machine Issues

Technical errors happen but they shouldn’t stop you from running your business smoothly.

Here’s what to do to ensure you keep potential glitches to an absolute minimum:

Keep software and firmware updated: Enable auto-updates and regularly check for new features or releases.
Charge your devices fully before use: This is especially important for mobile and outdoor trading.
Clean and store equipment properly: Avoid damage from dust, drops or moisture.
Monitor payment reports: Watch for unusual patterns, rejected cards or terminal downtime logs.
Train your staff on proper usage: Ensure all team members know how to troubleshoot basic issues.

These tips will help ensure you keep downtime to an absolute minimum while allowing your business to flourish.

How myPOS Minimises Downtime for UK Businesses

Looking to get a new card machine that’s reliable, sturdy, and comes with exceptional support? myPOS is the trusted partner for thousands of merchants across the UK.

Our wide range of versatile card machines allow you to accept Chip & PIN, magnetic stripe, and contactless payments from debit cards, credit cards and digital wallets.

They also come equipped with the following features:

A SIM card ensures constant mobile network connectivity. This means you can continue processing payments even when there’s no Wi-Fi access.
Wi-Fi connectivity gives you a backup option for internet access. If the mobile signal is weak and inconsistent, you can switch to a stable W-Fi network to continue accepting payments without delays.
Long battery life ensures the card machine can operate through busy trading days without needing frequent charging. This reduces the risk of downtime caused by sudden power loss and is especially useful for mobile our outdoor payment solutions.
Sturdy hardware built with durability in mind withstands everyday wear and tear. This physical resilience minimises damage from accidental drops or spills, reduces repair needs, and thus spares the downtime needed for them.
The sophisticated software is optimised for speed, security, and stability. Features like automatic updates and error detection help keep the system running smoothly and ensure quick recovery times from any issues.

Additional features such as the multi-operator functionality and additional integrations also enhance myPOS card machines’ efficiency and limit the downtime risk for UK merchants.

Whether you need a portable card machine that allows printing of receipts or a countertop model with a power cable connection, we offer reliable and affordable options designed to meet your needs.

Conclusion: Stay Prepared and Keep Payments Flowing

Whether it’s poor internet connectivity, a hardware fault or a depleted battery, a failing card machine can seriously disrupt your business.

Fortunately, with the right troubleshooting steps, regular maintenance, and staff training, you can minimise downtime and keep transactions flowing smoothly.

Investing in a reliable card reader like those offered by myPOS ensures you’re always ready to accept cashless payments. Stay prepared, stay connected and never miss a sale.

Frequently Asked Questions

How to troubleshoot a card machine?

Start by restarting the device and checking your internet service provider connection. Make sure the card machine’s software is up to date, inspect the hardware for damage and confirm your merchant account settings. If issues persist, perform a test transaction and contact your provider for support.

Why are card machines not working?

Card machines can fail due to weak connectivity, outdated software, hardware damage or issues with your card processing setup. Environmental factors like dust or low battery can also cause disruptions. Regular maintenance and choosing a reliable internet service provider help minimise these issues.

What to do if a card reader is not working?

First, try a reboot. Then check signal strength, update the software and inspect physical components like the till roll and card slot. Ensure the reader is fully charged. If none of these steps work, reach out to your provider for assistance with card processing diagnostics.

Sources

Author

Desi Tzoneva

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