After having connection issues I decided to re connect my system. An article I read suggested installing with the router 5ghz temporarily disabled. Did this and all fine, enabled it and instantly get the message that Sonos and phone need to be on same network.
Message fix suggests updating network, I just don’t that to cause problems, if it’s the only way to go then ok.

Short of disabling permanently the 5ghz what can anyone suggest? Router is a Virgin Hub5, I’m sure their is a fairly simple answer to this, please!