Did you get a 1099-MISC or a 1099-NEC? They are different forms this year.
Second, do you do this activity regularly, with an intent to make a profit? That may be all that's needed to call it self-employment. For a hobby, you don't pay the additional 15% self-employment tax, but you can't deduct expenses. For self-employment, you do pay extra tax, but this goes to your credit at the social security system for future retirement and disability benefits, and you can deduct expenses.
