You may have accidentally made a mistake when creating the original receipt and simply need to reverse it and reissue it.
To begin, locate the deposit you'd like to reverse.
Open the sales record
Select Trust Transaction Inquiry
Open the deposit
From the cogwheel, select Reverse Transaction
The brackets indicate the negative amount to be saved
Save the record.
The reversal will be reflected in the Trust Balance.
You can now create a new deposit. Please note that the transaction date cannot be back dated to a prior month.