Cramps in the neck and tongue sometimes. What is this? How can I prevent it?

Since a year ago or so I started to have this occasional event of yawning (most often comes from that, but sometimes from putting my neck in a certain position) and I get cramps! It’s so annoying, and I have to struggle into positioning neck and tongue in a way that allows it to fade out without too much pain. What should I do to prevent this, and what is this anyway? Thanks