After two years of flying a P4 with zero issues, one of the firmware  upgrades on the controller and or aircraft has transfered the camera tilt scroll wheel to carry pan scroll wheel.  I have gone thru all menus, and settings and cannot get it back.. the finger touch on the iPad will still move it up and down, but not the scroll wheel.  For me, it  is absolutely essential for this control to control the camera tilt up and down.  Controlling the pan has absolutely no use manually.  
Any help or suggestions would be appreciated.  This had to be a result of engineered changes in the  firmware or  GO 4 application because the  menus have change when we could select camera control either  vertical or yaw previously

Hi there, we're sorry for the inconvenience caused. Regarding that can you please try to calibrate your remote controller via DJI Go 4 app? So we can check. Please keep us posted for further help. Thank you.