In App transactions review for Square I get this error:ErrorWe couldn't Add the transaction(s) due to "Code. Check account mapping in advanced settings and try again.

Hi there,

Welcome to the Community. It's important you're able to use QuickBooks without getting the error you've described above. I'll be glad to assist so you can continue to do the things you enjoy. 

Based on what you've shared, are you getting this error while using a private/incognito browser window? Also, I recommend checking the transactions and the mapping to make sure it matches your expectations. I also suggest checking to see if you have bank rules enabled. Banking rules is a feature that automatically categorizes your transactions for you. Here's a helpful article that provides more info about: Set up bank rules to categorize online banking transactions in QuickBooks Online. 

When it comes to moving the transactions to the right account, I encourage you to follow the steps in this article here that shows you how to categorize your transactions in QuickBooks. Give this a try and let me know how you make out. I'll be one message away in case you need additional support. Otherwise, I wish you a great rest of the day!