Thanks for reaching out to the Community, @5247719937350420.
Before going into detail, I want to ask if you're using the QuickBooks mobile app card reader?
If so, I've got some troubleshooting steps to get you back to business.
Let's go ahead and disconnect and reconnect the card reader.
Note: Before we begin, sign in to GoPayments or your QuickBooks Online mobile app as an administrator. Look at your app and determine if the color is green or blue.
For the Green GoPayment:
For the Blue GoPayment:
For more detailed troubleshooting instructions, you can refer back to this article as well: Fix issues with the GoPayment and QuickBooks mobile app card reader.
Let me if the steps above do the trick. If you have any more questions, I'm always here to help. Have a safe and productive weekend ahead!