Hi there,
I know how important it is to start your accounts off on the right foot. When you first start with an A/P or A/R account, you'll have to enter a starting balance. If you've entered transactions by mistake, I'd be happy to explain how you can delete them.
In this case, transactions will have to be deleted one-by-one. Simply click Account History from the Chart of Accounts list next to the account you'd like to fix. Then, click each transaction to open it. Click More at the bottom of the page, then select Delete.
I know how convenient it would be for you to be able to delete all of these transactions at once. I'll pass your feedback along to our product development team about this. We're always looking for new ways to improve QuickBooks Online.
If you have any other questions, please reach out to our tech support team.
Cheers.