Why can't I get on to my webinar?

My problem hasn't been spoken about so am assuming somehow my settings have been changed.

I am no longer able to reach any of my Silver  Sneakers classes on my android phone. This began happening this week. I have reinstalled both Zoom and Silver Sneakers. Instead of the assigned class, I  receive ads which I am told to install: incognito browser and some rock app. 

Please advise as to what is happening.