How to Change Receipt Amount in Receipts Workbench

Using Oracle R12.1.1.

Client entered a wrong receipt amount.  How can we modify the receipt amount to reflect what should be the correct receipt amount.

Receipt Method used is using manual document sequence.

If I try to unapply the receipt, delete it, and create a new receipt with the correct amount and the same receipt method, receipt number, and document number, Oracle errors out with message saying the Sequence number used is already existing.

Is there any way where we can modify the receipt amount?

Thanks