Float payments or receipts that have been posted incorrectly can be edited or deleted either from within the Bank Reconciliation or from the batch update screen.
Example - Bank Reconciliation - double click to open the transaction
Edit or delete and re-process
Example - batch update screen -
Browse to the Accounts tab
Select Update from the Batch area in the ribbon
Enter the date and select Prepare Batch (but do not update)
Double click to open the transaction
Edit or delete and re-process