An excess SEP contribution is subject to a 10% penalty calculated on Schedule A of Form 5330. TurboTax does not support Form 5330. To file Form 5330 you'll have to prepare it outside of TurboTax.
Note that since it's your responsibility, not the SEP-IRA custodian's responsibility, to track the year for which the SEP contribution is made, if the excess contribution originally intended for 2024 was made in 2025, you could potentially track it as a contribution made for 2025 instead of 2024 and avoid it being an excess contribution for 2024.
