Hello awebsdale,
Welcome to the QuickBooks Community. It's great to have you reach out to us here. QuickBooks is designed to help you streamline your work using the powerful features offered in the program.
In order to successfully edit your transaction, I encourage you to check out the following article that shows you how to: Find, review, and edit transactions in the account history in QuickBooks Online. In case the transactions are reconciled, the article also shows you how to deal with those aswell.
Let me know if this info helps. I'll be one message away in case you need anything else. Otherwise, I wish you a great rest of the day.