sonos amp connection problem

Hi, have spent 3 hours direct with Sonos doing all testing to try and fix this issue.

I had no issues with my 3 connect amps on S1 and a new Sonos AmP on S2.

recently I switched my power off and had to reset all the amps which went from being wireless to now connected directly to my sky router.

the 3 connect amps all connect to S1. The new Sonos Amp did connect to S2 but then disappeared.

have done hard resets. turned everything off, including router. But each time the Sonos amp will not connect to S1 - it can find it but then says problem identifying it in set up try again. When I try to set it up in S2 as a separate system it asks me to so to S2 beta. Each time it asks for an 8 digit pin it says will be in the side or back of the amp - which Sonos themselves have agreed does not exist.

without said pin I connect even connect it to s2 now.

so o have no way to connect it to S1 or S2. 
 

help appreciated as Sonos have done everything they know.