I saw some people having this problem a couple of weeks ago but it was only yesterday that it happened to me. I'm locked out of the game I'm in, as in I can open the app and do other things in it fine but just can't play in the game. I have emailed about this but was wondering if anyone else was still (or newly) having this problem?

Do you have chat notifications? If so open the game room you are in and quickly press the home button while the game room in loading. This should clear your chat notifcations. Then reopen the app and it should work as it worked for me.

Do you mean press the home button on my phone? If you mean an in-app home button I'm not sure what that is.
Also, I managed to find a solution (of sorts...) which was to let myself get autoresigned and for some reason when I opened the game again straight after that it not only worked but I was un-autoresigned and able to play again. Pretty weird...

Actually I've figured out what you mean But no, I tried that and it didn't work. Notifications were cleared but it still crashed every time.

Have you tried using a cleaning app and cleaned your memory and cleared your cache? I used Battery Doctor.
That helped me when I did it, although I had iPhone 4s iOS9