EE digital phone adapter stopped working with corded phone

[markt99]

My mother has an oldish corded phone plugged into a EE digital phone adapter which went dead, no dial tone, would not ring and could not make calls from it, but the EE adapter it was plugged into was still showing a solid aqua light. 

I tried switching off the adapter and switched it on again at the mains socket, it linked with the EE hub again and a dial tone returned and I could make calls with the phone again.

Another corded phone she has plugged direct into the EE hub didn't stop working during this time as well as an older BT digital voice cordless handset which also kept working with the EE hub.

But what went wrong with the phone connected to the EE wireless digital phone adapter ?

[JimM11]

@markt99 No way off knowing why the adapter stopped responding, but here is the info below on what the adapter lights mean, so take a look at that when it stops responding the next time.

What your Digital Voice
Adapter light means
1 On initial plug in – flashes 0.5 seconds on,
2 seconds off
2 During registration – flashes quickly
0.5 seconds on, 0.5 seconds off
3 Once registered – stays solid green
4 During a call – flashes slowly 1 second on,
1 second off
5 Once registered, if there’s a connection
problem with your broadband – flashes
0.5 seconds on and 2 seconds off.
Maximum Digital
Voice devices
You can register a maximum of 5 Digital Voice
devices (that includes Digital Voice Handsets
or Digital Voice Adapters) to your new Hub at
one time