For those who have issues with manually entering the expiry date of credit card, I just deleted the app and reinstalled it again and it worked.
Thank you for taking the time to share this tip @Petalino! These payment troubleshooting steps should help, and as you mention and so will deleting and reinstalling the app - provided you haven't taken any payments in Offline Mode.
For anyone else reading this the steps to manually enter a card payment to your Square app are in our Support Centre.
If you have any more tips feel free to share them with the Community!
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