@5_19  As stated above, no one here or TurboTax can cancel your return.  If you have not filed your return yet & you are using the Online version, you can use the Clear & Start Over option in TurboTax.  Then just abandon the account.

As long as you haven't submitted payment, deducted the TurboTax fee from your refund, or registered, you can erase your return and start from scratch in TurboTax Online.

How do I clear and start over in TurboTax Online?

https://ttlc.intuit.com/community/using-turbotax/help/how-do-i-clear-and-start-over-in-turbotax-onli...