Adding Google voice assistant

Nearly two weeks ago from evening to next morning my Google assistant stopped working and impossible to add it again. I’ve rebooted sonos, unplugged and plugged back my router, it’s linked to the speaker via google assist but I keep getting message “no devices founds - make sure that your wifi is on and that your ihone and assistant devices are on the same network then try again”. Wifi is on, devices are on same network - i hadnt touched or changed anything in the time it stopped working.  Am not sure what else can do so please advise.  I tried calling customer support to find i was number 70 in the queue.  You don't monitor your email support anymore so no way of getting in touch with a human being which is incredibly frustrating.