How to Gimbal Control Setup

Hello. I’m a starter PX4 autopilot and have some question.
I have a gimbal and could operate with ardupilot.
That means, gimbal’s servo move when I tilt/roll Pixhawk Cube,

In autopilot, I couldn’t do that.

https://dev.px4.io/master/en/advanced/gimbal_control.html
I refered above page,
set MNT_MODE_IN to AUTO
set MNT_MODE_OUT to AUX
Because, the page say
’ If the output mode is set to AUX , a mixer file is required to define the mapping for the output pins and the [mount mixer] is automatically selected (overriding any aux mixer provided by the airframe configuration).’

But I couldn’t check any servo move.
Next, I tried ‘Loading a Mixer’
typed ‘mixer load /dev/pwm_output1 /etc/mixers/mount.aux.mix’,
using MAVLink Console in QGroundControl
pwm_output1 = AUX PWM (pwm_output0 = MAIN AUX)
mount.aux.mix = Mount Mixer
After typed command, I couldn’t check any move too…

What should I do in this case?
Did I miss something?
Please advice for me, setting, configuration, anything.