I have a Mitsubishi mini split (MSZ-GS series) with 5 indoor heads. I bought 5x WF-2 adapters, and following the instructions, was able to install and configure 4 of them. The 5th of them gets stuck at the very last step of configuration in the Kumo Touch app, "awaiting system configuration".

I tried removing the WF-2, factory resetting it, adding it again: same result.

Mitsubishi's docs at https://help.mitsubishicomfort.com/kumocloud/connectivity#what-do-the-different-steps-mean-as-i-go-through-the-process-of-provisioning-and-connecting-kumo-cloud-to-my-wi-fi-network-1 say a problem at this stage is "likely a network problem".

I have this WF-2 set to associate with a WiFi SSID that is 2.4 GHz only and the other 4 WF-2 units are using happily. It is receiving an IP address via DHCP and I can see it in my network management interface and ping that IP address. I can ssh into the access point and run tcpdump and see this WF-2 unit exchanging HTTPS (port 443) traffic with a few servers in AWS, so probably the cloud side of Kumo Cloud. This is all to say, it doesn't look like a network problem on my end.

Any ideas what could be wrong or what troubleshooting steps I should try, or is it possible this WF-2 unit is defective?