If your commission income is reported to you on a 1099-MISC, then you should be able to deduct these payments   from your income ("Income you Gave Back"). See the attached screenshot for where to find this entry in TurboTax Self-Employed. 

This entry is a Business Income entry, not a "gift".

Thank you for your time, the attached screenshot will not open? I would like to know where i enter this. Look forward to hearing from you again.

Do I list it under commission expenses?

misc expenses titled income given back?

I've replaced the screenshot. You could also list as Misc Expense, "Rebates"

Thank you!