S.A.M Challenges - how to take part in them?

In spite of playing with internet connection, and being able to activate SAM once every 4 hours or so and doing it on a daily matter, I was never given any gift rewards.

It's as if I'm out of the entire S.A.M challenge system, which obviously hampers my experience greatly.

Does anyone know a fix for that?

I'm not sure if you're doing something wrong or if this is a glitch, but just to recap: S.A.M. unlocks once every day, to get the special S.A.M. gift you have to get it every day for 5 days straight. You wrote that you can access S.A.M. every 4 hours or so, if this is true, then something is obviously very wrong with Jetpack Joyride on your divice. I hope I've at least helped a little