Two different Tapo Smart plugs, both a P125M greyed out in HA for no apparent reason. The Tapo iOS mobile app shows the devices still and they worked from the Tapo app but no longer work in HA. HA only shows them as, "Unavailable". Searching on that suggests you use the "reconfigure" menu to sign out and back in again essentially to Tapo cloud. However, that entire dialog gets stuck on the IP address field and I am not able to get past that. The reconfigure dialog shows the correct IP address and that even matches what the Tapo moble app lists for their static IP's on my network BUT I can't get past that since it's an apparent BUG in HA; it won't get past asking for the IP address. That dialog seems completely unnecessary to ask in the first place and it has become bugged now.
If you have found a problem with the official HA integration for Tapo, there is a link to issues and feature request in the HA docs for the integration, I would start there. You can create these as well from there.