It makes sense to me insomuch as it confirms that there are those who will never be able to grasp the most basic concepts of technology.
It must be a puzzling world for them.
But, like you, I'm intrigued about how they plugged a digital voice DECT phone into anything.
sorry but you are not giving enough information to help you if you check message 12 does your 'white box' look like that?
If you have an ONT, the hub should not be connected to the NTE 5c.
Have you checked in the hub manager whether it shows a a phone number or says not configured?
Optical Network Terminal
It converts the optical signal to an electrical signal to connect to your hub.
Can you answer my previous question please
If you want help you need to answer the questions.
The hub manager is http rather than Https as it is only accessible within your secure environment.
The hub manager is there for your benefit to administer various options.