Hexacopter not stable

I have designed an hexacopter by myself, i made the URDF and it is spawning correctly but when i give the takeoff command, upto certain height it goes then become so unstable that ultimately crashes. I have checked multiple times, channels seems fine to me, liftdrag plugin for all 6 rotors are also seem fine to me, inertial and CG is also at good place, changed the param file for hexacopter X frame type but getting same result. I even checked the log files just before it started to get unstable it always shows “ekf:yaw reset”. Can someone please help me out in with this gazebo simulation.

It probably has something wrong, misconfigured, bad tuning or bad vibrations. Could even be a bad esc or motor. Maybe the radio has something not right or the battery could be the prob.
Never find my crystal ball when i need it…

EKF Yaw messages are OK
We can only find out more from a .bin log file.
Upload one to a filesharing service like dropbox and post the link here

@xfacta Thank you for reply, Here is the google drive link to log file, by the way in this topic i am talking about simulation only

@MshUav actually i am talking about the gazebo simulation only

Ah ok, you are asking why a urdf file is not working.

Maybe should go in here: Copter Simulation - ArduPilot Discourse

@MshUav thank you for the direction