Why my iPhone can't connent to WIFI?

Here is the thing ..

My iPhone 5 can't connect to WiFi networks ..

Always showing "Unable to Join (xx) network" ..

It can only connect to Mobile Hotspot networks ..

And that's weird .. if it can connect to one network why can't connect to other networks !!

I've tried to Restore it .. but that didn't help at all.

So, if someone have experienced that problem pls tell me how to fix it.

Thx in advance.