Stuck in FaceTime

Okay so I’d call someone on FaceTime but when I try to hang up it says “FaceTime Ending” so I stay on the screen waiting for it to end but after many minutes it still doesn’t end it just shows I’m still on a call in the top left and I can use my phone. But the thing is when that happens I go home and try opening apps and it won’t let me, I can reply to texts from the notification bar but can’t open any apps unless i was previously in it and can go back into it. Using the “Swipe up from the bottom and Hold onto it” to go back into my recent apps. Other then that my phone is useless. If I don’t have any apps previously opening meaning I closed all my recent apps and I can’t open any apps or answers any calls period. The only solution I have is to wait for the phone to die since I also can’t restart it using the bottom volume button and the lock button and holding them. But it’s kinda an issue not being able to charge my phone cause I have to wait for it to die and restart on it’s on again. Since I can’t do it manually. This is happened 3 times already within the past week and I’m tired of it. Any help?!?