I want clean our database and start a fresh new installation with the same subscription. Because I used to testing features.

Log in to your QuickBooks.
Navigate to your homepage.
Replace the end of URL from homepage to purgecompany. See example below:
From: https://qbo.intuit.com/c28/app/homepage
https://qbo.intuit.com/c28/app/purgecompany
A pop-up screen will show a summary of the items to be deleted.
Enter the word “YES” to delete the data.
Click OK to complete the process.

Once done, click Wipe Data. You'll then be rerouted back to your homepage. If you are using QBO Simple Start or the account is more than 60 days old, you have to open a new blank QBO account.

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