Ok I'm dumb. Show subject field must only work for iMessages. That's the problem here. If not go to
1.settings
2.general
3.reset
4.reset network settings
This will delete absolutely nothing. You will only have to reenter wifi password if needed. THATS ALL IT DOES I PROMISE IT SHOULDNT DELETE ANYTHKNG ON YOUR PHONE WHATSOEVER
1.settings
2.general
3.reset
4.reset network settings
This will delete absolutely nothing. You will only have to reenter wifi password if needed. THATS ALL IT DOES I PROMISE IT SHOULDNT DELETE ANYTHKNG ON YOUR PHONE WHATSOEVER