Zwift Companion App not working on iPhone if you are using iPad for Zwift Ride

Hi All,
I have been using the turbo trainer in my gym lately when I can’t get home to use my own, so I bring my iPad to run the zwift game and my iphone to use the Zwift app, even though I am on the same Gym WIFI when I look at IP Address on iphone and ipad they are different IP addresses - the app will not recognise I am on Zwift? Has anyone had this issue or overcome this issue - its very annoying as I cannot seem to be able to join in conversation, give Ride Ons etc! any advice would be great. Thanks Muriel

On public WiFi they could have it set to isolate the clients so they cannot communicate with each other.