Flight modes are not working

Hardware Pixhawk family
1

I am using pixhawk and in mission planner, I have set 3 flight modes Stable, RTL and loiter. But for some reason when a flip the switch to change the flight mode on my Taranis X7, the modes don’t change.
Are there some other settings to be done?
FLTMODE_CH is 5.

2

see: https://ardupilot.org/copter/docs/common-rc-transmitter-flight-mode-configuration.html#common-rc-transmitter-flight-mode-configuration

and

https://ardupilot.org/copter/docs/flight-modes.html#full-list-of-flight-modes