Tailsiter/ quad palne motor randomly ramping down/ not working in qloiter,qhover and auto

hello,
i recently has made a tailsitter quad plane. I am facing problems that the motor in qloiter, qhover,auto are not working. problems encountered are:

  1. motor not spinning in random sequence
  2. random motor in flight slows down and stop causing a crash
  3. in FWB roll and pitch controls are not responding

what has been done:

  1. change motor- same issue
  2. esc calib- same issue
  3. change pixhawk- same issue

note : in manual mode the quad sitter perform great and no issue is found

link to the bin file:
https://drive.google.com/file/d/1pvJUQx4qQAYjZmwwunEe9XSUsYgqURE5/view?usp=sharing

any help will be much appreciated
thanking everyone in advance