I know how to prevent it but somehow someone ended up getting past my frames and in this north south/reverse mount sort of position where they were on there knees, and there crotch was in my face. Any tips on how to escape it and prevent it even further?

Everytime I go to headquarters I either get armbared or triangles. How do I prevent this.

So in no gi when I go for a kimura in closed guard I lock the grip then the other person grips btoh hands together and then I can't move it. How do I fix that?