OpenGrab EPM V3 not working in auto mode

I’m using a nicadrone opengrab V3 epm with a pixhawk in PWM mode.It works flawlessly with servo9 and a 3 position switch.on taranis.But,When I configure in mission planner for auto mode and program a mission it never releases the cargo.I’m using copter 3.51 and the latest mission planner.I have tried DO-SERVO and DO-GRIPPER it does not matter.
Can anyone who has successfully configured the EPM,please chime in.

SOLVED…
installed on RC9 on pixhawk.works flawlessly in auto mode now.