Unable to start offboard mode. RTL after arming

I am trying to start the offboard mode in this example: https://github.com/PX4/px4_ros_com/blob/master/src/examples/offboard/offboard_control.cpp
as specified by Nuno Marques here:

However, everytime I run the example, I get:

INFO [commander] Armed by external command
INFO [navigator] RTL: landing at home position.
INFO [logger] Start file log (type: full)
INFO [logger] [logger] ./log/2021-01-20/13_17_46.ulg
INFO [logger] Opened full log file: ./log/2021-01-20/13_17_46.ulg
INFO [tone_alarm] notify negative
INFO [commander] Disarmed by auto preflight disarming
INFO [logger] closed logfile, bytes written: 753394

So, it lands to home position right after arming and then gets disarmed right away.
Both COM_OBL_ACT and COM_OBL_RC_ACT are disabled.