The K-1 visa is only valid for 90 days, and it requires you to marry the original U.S. citizen petitioner within that time if you didn't marry within 90 days, you're now out of status and subject to possible deportation.

You cannot marry someone else and adjust your status from a K-1 visa only the original petitioner can sponsor you for a green card under the K-1 rules.

If you did marry the original petitioner, but just late (after 90 days), you may still be able to file for a green card, but you can’t adjust status through the K-1 pathway. You’d need to file a new petition (Form I-130).

If you’re now married to someone else (e.g., a U.S. citizen), they must file a new I-130 petition, but you overstay could make the process more complicated.