Hi there, Saphire605.
I'm glad you reached out to us for help with recording a lost check from last year in QuickBooks Desktop. Let's get this sorted out.
Thank you for those details, it's very helpful. In this case, you can create a deposit with the current date to offset the transaction. Just make sure to choose Accounts Receivable when creating the deposit, so you can link it to the invoice. Then, you should delete the credit memo.
To create a deposit, please follow these steps:
Then, here's how to link the invoice to the deposit:
I've attached some screenshots to help you with the process.
As a reference, you can check out this article for further guidance: Link a Deposit to an Invoice.
This should point you in the right direction. Keep me posted on how this goes. I'm always here to help. Have a wonderful day.