No wifi when iPhone 5c put on airplane mode for few days then off?

Hello, I have been using my 16gb iOS 8.4 iPhone 5c for some time and its been having some wifi issues (was working before this happened). It started when I was at a camp for a week and I put my iPhone on airplane mode for about 3 days. When I came home I turned off airplane mode and tried to connect to my wifI and I noticed my wifI wasn't showing up. I was like "What, this is weird?", so then whenever I go out to places with wifi that my iPhone recognizes, it doesn't show up either. So then I got a new router and tried to connect to it and it did. It had 2 connections to it and I connected to one of them. Next thing you know the other connections is gone when I connected to one of them. I am also noticing that when this happened some of my apps on my iPhone wouldn't use wifi or LTE like App Store, Instagram, Snapchat, Gamecenter, and some of my games too. If any you guys have the same problem or know a way to fix this then please reply. Thank you!