You may be disconnected for one or more of these reasons:
1. You have WiFi disabled: go to your phone´s settings and activate it.
2. You have disabled EveryFi: activate Auto-connect from the Settings screen.
3. You are not close enough to a known WiFi hotspot: use the map to find the nearest WiFi hotspot.
4. You don't have Fon credits: if you've already used up your monthly free 300 MB or –if you are a subscriber– your 5GB, you won´t be able to connect to Fon hotspots: use the map to find hotpots in bars in restaurants where you will still be able to enjoy unlimited free WiFi connections.