Hi there, @SuperiorGCAZ.

Thanks for joining the thread and sharing the error message. I've got the steps to help you undo and correct this transaction in QuickBooks Desktop (QBDT). 

This error usually appears when the transaction you're trying to delete was deposited to Undeposited Funds before it was moved to the correct bank account. To clear this out, you'll have to delete the deposit first from the Make Deposits window. 

Let me show you how:

1. Go to the Customers menu and select Customer Center.
2. Click the name of the customer, then look for the invoice payment. 
3. Right-click the transaction, choose View Transaction History.
4. Select deposit transaction under the Type column, then click Go to.
5. Press Ctrl + D on your keyboard. This will open a prompt that will help us delete the deposit. Select OK to confirm.
6. Click Save & Close, then open again the invoice payment and select the Delete button. 
7. Choose OK to delete the payment and select Save & Close.

This should now completely delete the payment. Once done, let's proceed to delete the open invoice. Then, recreate the transaction and record the payment to correct customer.

Lastly, perform a mini reconciliation method to fix your reconciled account. 

Moreover, you can check out this guide anytime you need help doing or fixing a reconciliation in QuickBooks: How to properly reconcile accounts in QBDT.

You’re always welcome to post again in the Community if you need anything else. It’s my pleasure to help. Have a fantastic day!