@sinemaker I went through something similar, where we added five new units to an existing, working-with-Kumo-and-HA system. For some reason, the new units had incorrect IP addresses after adding them to the integration.
Unfortunately, I don’t remember the full details, and I rebuilt my home network around the same time, changing IP address ranges and VLANs. So it’s possible that some of the issues I experienced weren’t Kumo or the Wi-Fi interfaces at all.
What I do remember is that I had to hand-edit the Kumo Cloud integration cache file, kumo_cache.json, and change the IP addresses for the units’ interfaces. The original, working unit had the correct address, but the other units had addresses from a different private network range (presumably from some default or temporary condition during setup).
Once I did that, and set the Kumo integration to prefer the cache file and rebooted HA, it all started working fine. (Or so I think I seem to maybe recall.)
The IP addresses can be hard to find in the long JSON file, but they’re under the key “address:”, and that’s the only key used for that purpose. (I think.) So, just do a quick search of the cache file for that key, and see if the addresses match what you expect. (And set the integration to prefer the cache file, and reboot.)