Why can’t I save Invoice? There is a message prompted “Please enter an account number”.
Acc No. is not selected /empty in Invoice.
You will need to assign Acc No. for posting.
You may pull out Acc No. column at Invoice and key in / select your posting account.
To pull out the column of Acc No., you need to go to Column Chooser (1), click and hold to pull out Acc No. (2) . You may save layout (3) if you want to keep the modified layout.
You may select the account number for posting purpose and proceed to save Invoice.
You may refer to the below link for how to create or manage your Product Posting.
https://help.accounting.autocountcloud.com/support/solutions/articles/69000387030-product-posting