I realize this a a bit of a newbie question....
I am having trouble descending with permission of the P2A ATC. During the initial flight plan, I include both my proposed SID and STAR, which gets programmed into the FMC. While flying I usually receive confirmation of the STAR and receive permission to fly it. When the FMC begins the descent, I usually receive another message from the P2A ATC that I am too low and I need to return to my cruise altitude. So, if I receive permission to follow the SID, do I also need to ask permission for this lower altitude as well? Shouldn't this be assumed and happen automatically?
Ron