Apps not working and error 9999 9100

My phone 6 running ios version 10.2 (14C92). Model NKQJ2ZP/A

It was working fine until the last couple of days. None of my banking apps are working and then a couple of others started playing up. I have restarted, force restart, deleted and synced phone etc. It is also happening on my ipad. I've had nothing but trouble with this phone. I love apple but this one has been replaced, froze and I had an hour long call to fix it, now this. Can't wait for my contract to be up to get rid of it.