Unable to set the servo configuration, Help needed

I am using Pixhawk autopilot on a Raptor G4, fuel powered, Flybar system. The problem that i am facing is that i connected the servos in the “main out” of the servo rail in the following configuration as mentioned in the manual available at arducopter website (1-Aileron , 2-Elevator , 3- Collective Pitch , 4-Rudder , 8- Throttle ). But the problem is that servos are not behaving as they are supposed to, e.g the elevator is acting as pitch, moving the aileron control on the transmitter just moves 1 servo, the throttle servo is not working at channel 8 . Moreover in the “radio calibration” option the channels there are also not behaving the way the are supposed to moving the pitch also moves the aileron.
I am using a Futaba transmitter and an SBUS Futaba receiver. Due to the above mentioned problem i changed the transmitter and the receiver I used a JR transmitter with a “JR RD921” receiver. The difference was that during “radio calibration” the transmitter was working absolutely fine but when i connected the servos according to the manual they were not moving and the same issue was there as mentioned above.
Kindly guide me if u can
Thanking in advance friend

You have to calibrate your radio first. Futaba or JR - both work just fine.

You need to set up a function on channel 8 that is used for throttle. You can then set up a switch on your Tx to give a constant output to keep fixed RPM.

When you get to setting up the Pixhawk your other channels are completely selectable if you look through the full parameter list. It is easiest to fly have a flybarless head.

Don’t be discouraged. With a bit of tral and error you’ll get there.

Have a look at Setting up a Traditional Heli in Mission Planner (FW3.3.3)