OvmsPoller vs `can can1 tx`

Hello,

I am having some creating a vehicle module for a new car.

Here's what I currently have :

OvmsVehicleVWID3::OvmsVehicleVWID3()
  {
  ESP_LOGI(TAG, "VW ID3 vehicle module");

  RegisterCanBus(1, CAN_MODE_ACTIVE, CAN_SPEED_500KBPS);
  PollSetPidList(m_can1, obdii_polls);
  }

static const OvmsPoller::poll_pid_t obdii_polls[] = {
    {0x17fc007b, 0x17fe007b, 0x22, 0x1E33,        {  20, 20, 20, 20}, 0, ISOTP_STD},
    POLL_LIST_END
  };

Using OVMS's `can log start tcpserver transmit gvret-b :23` and Savvycan, I can see my message being sent out every 20 seconds as expected. However, there is never a reply from the car.

When I execute `can can1 tx extended 0x17fc007b 03 22 1E 33 55 55 55 55`, I can see in Savvycan the exact same message as sent from the OvmsPoller, but this time the car will also reply (that second message starts with 0x17fe007b.)

Is there a difference between the message sent via CLI and the one sent via my code ? In Savvycan, as far as I can see both are exactly identical.

Thanks