How to regain use using WIFI

I have a problem using my Maestro C .
It has functioned properly on many occasions prior to my attempt to give a demonstration at a senior center. I was told to use "guest" to access their Wi-Fi system. I was not successful. I started pushing buttons and from that day since it has not worked.
When connected to my LAN with my 6400M, Tuner Genius, and Power Genius XL it works
totally as it should. Now, connected using WI-FI it appears to be connected. The screen boots up with "SmartLink' showing but no functional information and no buttons or knobs effect the screen. (it looks just like the 6400M screen just before the screen becomes active). I am running the same current version of software on both units. Any help will be appreciated.
Jim wb3dju