Doing kickflips/heelflips instead of ollies?

I've had this happen to me throughout the last couple weeks or so occasionally but it seems to be completly random and irritating. I'll be tryting to do a boned ollie to grind something an it will do a flip trick and ill crash instead. It gets old really quickly espiucally considering im tracing the exact line for an ollie. Has anyone else had this problem? how do i fix this without chaning how ive been playing the game. And it is definitley not me, i watch my right stick as im doing it and it even shows me going straight up and down. Please fix