If you are using QBO Simple Start, you are unable to purge your account. You should cancel your QBO account and open a new blank QBO account.
https://quickbooks.grsm.io/us-promo
then utilize the trial version of a 3rd party backup restore app during your setup
https://rewindio.grsm.io/quickbooks
If you only need to delete (not make it inactive) an item list (i.e Customer) with no historical data, utilize a deleter tool
https://transactionpro.grsm.io/qbo
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