Iphone 5, Minus button defect?

Recently updated to the latest IOS software on my Iphone 5 (Not S) And the minus button has completely stopped working! My phone is well looked after ie big case & Protectors so no damage, the only explanation would be the update! Any remedies?

Firstlty reinstall it to the basic mode and made it upggrated by some proffesinols…

If you have all your files backed up i would suggest a a full restore using itunes with the phone actually plugged into the computer.

The recent updates have had some notorious affects on handsets. I would suggest a back up and a full restore to factory settings. Try and see if the minus button works as the handset will be reset to factory reset with nothing on it at this point. If that works then i would restore from back up (one you created before restoring) and seeing whether it works. Obviously, if the problem still persists then I would revert to Apple for further investigation.