Hello there,
I’m very sorry for missing this post then you wrote it. I’m not sure if you got your questions answered through our support email or phone line, but just in case…the ZBMPlug15 is an HA certified plug and uses the default HA link key to join HA networks. Your network must be using the same key for the device to join.
The default HA key is 5A6967426565416C6C69616E63653039
I hope that helps.