Thanks for posting in the Community, JVK.
I'd be glad to address your concern in regard to converting a deposit into a bank transfer.
You'll have to manually delete the deposit and record it as a bank transfer to correct this. You can refer to this article for handling a bank transfer: https://community.intuit.com/articles/1146103.
Once done, I'm confident that moving forward you'll be able to handle this kind of situations and ensure your books are accurate.
Please don't hesitate to reach out to me if you have any other concerns by commenting below. I'm just a post away. Stay safe!