Servo Gimbal Yaw not stabilizing

ArduCopter
,
1

I have a servo gimbal connected to rc main out 1,2,3.
The pitch and roll axises stabilize fine.
I have used rc channel 7 to control pitch.
I have used rc channel 8 to control yaw.

The yaw servo moves when the potentiometer on the transmitter is moved, but doesn’t auto stabilize.

I tested this in althold and stabilize, where only yaw did not work.

Thanks in advance!

2

Update: the pitch servo also moves at a lesser scale, but corrects - just not at the correct angle

please help (I dont know if i should be pinging or not)
@rmackay9
@Yuri_Rage