Mute button locked during calls so i can't speak. How do i fix this?

Whenever i make or receive calls. I can't un-check the mute button. I can hear perfectly fine and i can record with the mirophone. It's only during calls on my apps whether it be normal calling, facetime, or whatsapp. The weirdest thing is the phone was working fine this morning and out of nowhere this started happening. Restarting phone doesn't work. Resetting all settings doesn't work either. Please help!