Can you explain this a bit more? Are you having an issue charging a customer's card or are you trying to link a debit card for Instant Deposit?

If you're referring to Instant Deposit, check out this troubleshooting article: https://squareup.com/help/us/en/article/5440 And if the ZIP code still doesn't line up, you may want to check with your bank to make sure they have the correct ZIP code on file.