Hi, I had the same Problem and could solve it with this post:
https://community.home-assistant.io/t/cover-entities-stopped-working-with-2021-6-update/314957
I had to update my zigbee2mqtt plugin + repository path, therefore I did:
- stop and uninstall the zigbee2mqtt plugin
- add the new repository path on the plugin side.
https://github.com/zigbee2mqtt/hassio-zigbee2mqtt
- install zigbee2mqtt from the new repository
- copy the old zigbee2mqtt configuration files from /share/zigbee2mqtt to /config/zigbee2mqtt. See: Updating zigbee2mqtt when i've installed from an old repo - #3 by dawsonweb
I used the samba share plugin to do this via my Laptop. - Start the plugin. Everything should now work like before
I hope this helps you!