Sometimes the "Cancel" icon is engaged, which makes it impossible to cancel the deposit slip.
This is the case when the period in which the deposit slip to be reversed is in a closed bank reconciliation. It is not necessary for the slip to be selected as part of the period's revenue in the bank reconciliation to prevent its cancellation. In fact, it is sufficient that the bank reconciliation for the period in question is completed and closed to prevent the transaction from being reversed.
Result:
In order to make the "Cancel" icon available again and to be able to cancel the deposit slip, the bank reconciliation of the period in which the payment in question is located must be reopened.