My spouse and I were divorced in 2020 and will be filing separately in 2021. I received a stimulus check and sent her half of the payment. Is there a form needed?

I received a stimulus check in 2020 and 2021.  My spouse and I were separated but filed Married in 2019.  I do not qualify for the stimulus check as an individual.  Will I need to send the full amount back to the IRS on my 2021 return, or is there a form that can be completed to show that the stimulus was partially transferred to my spouse?