Offboard mode start command error

Hello,

I recently switched to ardupilot and the mavsdk offboard mode isn’t working. The code is erroring at the start command:

raise OffboardError(result, “start()”)
mavsdk.offboard.OffboardError: UNKNOWN: ‘Unknown’; origin: start(); params: ()

I am setting a setpoint before. I tried both PositionYaw and VeloctityNED.
It worked perfectly with PX4 but something is wrong here. Any ideas? the error isn’t saying much.