AZ IoT Hub Edge Device can't pull Image from ACR

Question

I have an individual IoT edge Module, simple python code, packaged in a Docker Container and placed in an ACR registry.

When installing the module on one of my Edge Devices, it return Reported by Device = No.

• I have provided ACR credentials to the config file.

• OPC publisher is running on the same edge

• the VM behind the edge device is an on-prem VM behind firewalls, but IoT Hub and OPC communication is working

• I spin up a second Edge w/ a Cloud VM and try to set up my module there as well. And it worked for a Cloud VM.
  

Now, did I forgot something, any ideas why this set-up is not working and the Edge Device can't pull the Image? Does it may has something to do w/ firewall settings. As far as I understand the procedure, is that the IoT Hub setup is there to exactly clear these issues out.

thank you all