I did this and it wasn’t the problem ,so i fixed it and will post as it just might help some else . I had a top gun joystick that i use to taxi with some aircraft as a tiller. So what you do is in control Options --me it was my trim wheel on all aircraft the trim wheel was travelling by itself to the full down position --In the search box put in Trim - then i scrolled to Bravo Throttle Quadrant and i had Joystick button 23 and 22 in but it still didn’t work -so when i went over to my Top Gun joystick i noticed it had an Axis assigned to it trim down do it was conflicting so i deleted it and all is fine ,how it got assigned there i don’t know .