Sending Trajectory Setpoint for Multi-drone PX4

I am trying the offboard_control example at px4_ros_com/src/examples/offboard/offboard_control.cpp at px4_ros_com/src/examples/offboard/offboard_control.cpp at main · PX4/px4_ros_com · GitHub. I am able to control the drone trajectory from the topic fmu/in/trajectory_setpoint.

However, when I try the multi-drone configuration and the topic becomes /px4_1/fmu/in/trajectory_setpoint , I am not able to control the drone even after I change the topic in the publisher to be the new topic. I am using the below command to instantiate the SITL for multi-drone:

PX4_SYS_AUTOSTART=4001 \

PX4_SIM_MODEL=gz_x500 \

./build/px4_sitl_default/bin/px4 -i 1

I have modified the topics in offboard_control to the new topics with px4_1 prefix. I have also successfully sent a vehicle command by updating the target_system field.

Is there any other parameter to configure to send the trajectory setpoint for multi-drone configuration?

Thanks for your help.