Ignore user yaw input when ROI is set


I want to make sure the drone does not lose ROI because the user accidentally moved the yaw stick. I ran a SITL test with joystick connected to Mission Planner. Once the user input changes the yaw. the drone changes the heading toward the next waypoint. What changes do I need to make in the code to ignore the yaw input from the user once the ROI is set? or completely ignore the yaw input in auto mode?

Any help is appreciated. Thank you!