Quadplane moving sinus in waypoint route

Hi,i have a quad plane with 390 cm of wing span and 19 kg weight.when i want to fly in the route in waypoint and mission,there is roll and yaw correction and it is flying like sinus as you see in the picture below.the roll and yaw also constantly changed and the drone is trying to keep it self in the route.it is happened specially after bank turn from one point to other point,is ay one here can help me?



@tridge would you please help me in this issue??