When starting a new return, the online program transfers information from last year into the current tax year. Since you were self employed in previous years, it is upgrading you to the self-employed version when this data is transferred into the current year. To downgrade you can clear & start over and select "my tax situation has changed" in the beginning of the new return. From there you can select that you no longer have a small business. Below are some steps on how to clear your return if you haven't filled anything in just yet.
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