I've removed the router (forget) and reset my phone, and I even tried safe mode but my WiFi keeps disconnecting all the time. Does this mean it's a problem with my phone and not a third party app? If so how do I proceed?
Can you log into your router ?? This should tell you of what's is connected to it. Once there, see if your phone is listed as connected. If not, then you could do a network reset. This will erase all passwords and all saved WiFi. Then try again.