Welcome to QuickBooks Community! Having the ability to start fresh in your current QuickBooks Online account would be ideal in saving valuable time. However, the option isn't available for accounts that have been active for over 90-days. I'd be happy to provide you with other options!
In this situation, you can export the data from your current account and save it to a folder for easy access. Once you've completed the process, you'll want to proceed with cancelling your current QuickBooks Online subscription to prevent future billing. Keep in mind that you'll continue to have access to the data in the account for one full year from the cancellation date. When you open a new QuickBooks Online account, you can import your data by following the steps in this helpful guide.
If you have any other questions, please don't hesitate to reach back out. We're always glad to help!