Do Amended return? Began Social Security in 04/2024. Part A backdated to 09/2023. Already filed taxes and funded family HSA by $2050 for all of 2023, $2025 for 2024.

You can't contribute pre-tax dollars to an HSA after enrolling in Medicare Part A or Part B. This is because you can't have other health insurance than a HDHP to contribute pre-tax dollars to an HSA.

I know. SSA backdated Part A. Do I need to amend 2023 return with what I deposited. I believe I just need to remove funds for 2024. Thank you

Since you can’t contribute to an HSA while covered by Medicare remove any contributions that applies.