Netatmo Presence Camera cant be installed with iOS 15.3.1 and HomeKit

Hi we are desperately trying to install a new Netatmo presence with iOS to HomeKit. The Netatmo security app takes me to the screen where it recognises the HomeKit house name then the next screen just has an "unknown error" and we cant proceed with the installation.

Have read the advanced troubleshooting guide and disabled 5Ghz etc but cannot active the camera at all. Netatmo support seem to think thats its a known issue with iOS 15 and the WAC protocol in iOS.

They tell me the only way around this is to use an Android device! Absolutely crazy for what is supposed to be a HomeKit Certified product.

Has anyone else seen this or have another workaround? We dont have an Android device we can use.