The doubling is a result of a bug introduced with the February 8, 2024 update to 2023 TurboTax. Intuit is aware of the problem.
https://ttlc.intuit.com/turbotax-support/en-us/help-article/insurance-medical-benefits/turbotax-desk...
Note that your excess-contribution penalty will continue every year until the excess is corrected either by taking a taxable distribution of the excess from the HSA (which would also subject to a 20% for being under age 65) or applying it as part of an HSA contribution for the current year. Since you seem to continue to be eligible to contribute for 2024, just make sure to reduce the contributions for whichever of you has the excess so that the excess can be absorbed in 2024 (and hope that TurboTax fixes the bug).
