I have an open SSID for students in the dorms. When conncecting from mobile devices, students get message stating "No Internet Connection" with an exclamation point on the wifi icon. Everything has been working fine for at least a year, but all of a sudden, they can't connect. When I look into the controller, ALL AP's are up, and i can ping everything on my network from the controller when using the diagnostic. Not sure what is happening. Any suggestions?