Unfortunately, there is no way to downgrade a TurboTax product once you have upgraded it. You would need to create a new return and reselect the lower version.
Once you have started your new return, you can click on "View all tax returns" and click the small Trash Can next to the unwanted return to delete it.
Note: You may have been asked to upgrade to Self-Employed based on the information you have provided. If you've entered an amount from any of the boxes on the slips listed here, you have what the Canada Revenue Agency (CRA) considers to be self-employment or business income:
T4 slip: box 81, 82 or 83
T4A slip: box 20 or 48
T4A slip: box 28 and you selected Yes to the question Does the income declared in Box 028 consist of fees collected for services you provided? in TurboTax Online (needs to say NO to indicate no self-employment)
T3 slip: box 24 (foreign business income)
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