presumably you are 50 or older, so the limit is 8k and your earned income exceeds 8k so there are no complications in terms of the validity of the contribution. so what tax are you referring to, did you use this for a (backdoor) Roth conversion? If so the contribution in calendar year 2025 is not considered as part of your basis for the conversion so I think if you converted 8k only 7k will be considered nontaxable assuming your IRA had no prior basis/balance.
Form 8606 instructions line 4:
https://www.irs.gov/pub/irs-pdf/i8606.pdf
Although the contributions to traditional IRAs for 2024 that you made from January 1, 2025, through April 15, 2025, can be treated as nondeductible, they aren’t included in figuring the nontaxable part of any distributions you received in 2024
