Unallocate a receipt allocated to an incorrect invoice
From the main menu, select Bookkeeping > Cash Posting > Sales Ledger Receipts.
from the Client > Assignment window, click Sales Ledger.
In the Sales Ledger window, select the Show Zero check box.
Select the receipt that was incorrectly allocated.
Select the appropriate tax rate for the unallocated cash receipt from the drop down Tax Rate field on the Tax on Unallocated Cash window.
The receipt is now unallocated cash in the Ledger.