Hello,

If this Sales Receipt was put into Undeposited Funds and part of a larger bank deposit, it will have other payments in the deposit as well. (This might be why you're not finding a deposit for this amount)

Bring up the Sales Receipt and in the upper left you should see the deposit that this transaction was a part of.  (PICTURE ATTACHED)

Click the date to bring up the deposit.  Then you can uncheck this sales receipt from the deposit, resave the deposit and THEN delete the sales receipt.

Keep in mind though this will affect the amount of the bank deposit and possible reconciles if the deposit has been reconciled.