training a cat1 Training a cat how do I get him to roll over?
Ramses II asked:

I have been training my ginger tomcat Jonathan for the last 4 months, and we’ve mastered all the basics: Sit, Lie Down, Stay, Wait, Heel, Beg etc etc. He even does tricks.

But purchase prescription drugs without a prescription he won’t roll over, not even for his favourite treat of Friskies.

Any hints, is there a physical reason why a cat is so stubborn?
And yes, he is toilet trained.
Jonathan is very trusting and rolls over to display his belly of his own accord, but not on command, which frustrates me.