Why can my iPhone not connect to anything?

I have a fully updated iPhone 5s. All my software is up to date and I've only had it for two months. The only odd thing is that the home button can be twisted around and is lose, which I noticed shortly after I got the phone. This phone was a replacement by T-mobile after my other iPhone was stolen. The main issue is that as of recently I've been unable to use apps that require internet. They stop responding and I can't connect to the internet over wifi or data. I've tried disconnecting from wifi and data and reconnecting, and I've uninstalled snapchat and other apps that this always happens to. Sometimes I don't even receive texts or calls. What's the problem and what can I do? It's a new phone but nothing seems to be working unless I restart the phone. After restarting, everything works fine for roughly half an hour before I have to restart it again.