you can't stop his filing
you can call the iRS about this
800-829-1040
Report that your spouse filed a joint return without your consent. Write down the date and time of the call and the identification number of the IRS employee.
see this thread
https://www.encyclopedia.com/articles/if-my-spouse-filed-our-taxes-jointly-without-my-knowledge-what...
I suggest you seek counsel about what to do. filing as single is not an option since you were legally married on 12/31/2024
others may have their own suggestions.