Simulink flight control model test in HITL

Hello I have a flight control model developed on Simulink and I want to test on the pixhawk in HITL I build the model to the pixhawk and connect it to JMAVsim and QGrouncontrol to run in HITL mode as mentioned here ( but once I start the app no actuator command is being send to the simulation I tried to crate a model that send random PWM commands to the rotor and built it to the pixhawk and when I run on HITL nothing happen also the simulation respond to (coomander takeoff) and other commands but not to mine any help ??