The speakers are connected to some Sonos devices, likely an Amp but maybe a Port or Connect and an external amplifier. You need to find that Sonos device and make sure it is powered on and working.

Hi Thank you. Yes I have two amps one is working fine the other has dropped out and I can’t add on the app. Also can’t connect to WiFi. It was working fine up until two weeks ago

Unplug the "missing" Amp from power for 30 seconds  plug it back in and make sure the LED goes through the normal startup steps. Hopefully it will and you can then see it in the controller.

If the LED isn't normal or you can't see the Amp calling Sonos might be your best option.

Thank you and will try that!