Entity is currently unavailable/new Mesh

I am new and I don’t know anything about coding.

I installed Home Assistant Green, 4 days ago (I created scenes, automations etc). I also use nabu casa cloud. Everything worked perfectly well until I installed Deco 75 pro. Since then, the Google Cast and Shelly integrations no longer work. Therefore, Home assistant no longer supports media (nest, hub, TV). Only the box doesn’t have the message “This entity is no longer provided by cast integration”. I have the same problem with the Shelly module.
It seems that the IP adress changed (for the Sheylly device, I have the message host ssi=false, proxy=none)

I try to unstall File Editor but HA cannot open it. I have this message:

“s6-rc: info: service s6rc-oneshot-runner: starting
s6-rc: info: service s6rc-oneshot-runner successfully started
s6-rc: info: service fix-attrs: starting
s6-rc: info: service fix-attrs successfully started
s6-rc: info: service legacy-cont-init: starting
s6-rc: info: service legacy-cont-init successfully started
s6-rc: info: service configurator: starting
s6-rc: info: service configurator successfully started
s6-rc: info: service legacy-services: starting
s6-rc: info: service legacy-services successfully started
INFO:2024-04-15 08:38:49,811:hass_configurator.configurator:Starting server
INFO:2024-04-15 08:38:49,812:hass_configurator.configurator:Listening on:
INFO:2024-04-15 08:39:18,758:hass_configurator.configurator: - “GET / HTTP/1.1” 200 -
INFO:2024-04-15 08:39:49,017:hass_configurator.configurator: - “GET / HTTP/1.1” 200 -
INFO:2024-04-15 08:40:19,267:hass_configurator.configurator: - “GET / HTTP/1.1” 200 -”.

I restarted Home Assistant, activated and deactivated the integrations, without success.

On Home Assistant Cast, the devices are available and one of my dahsboards still casts on my Google Hub.

The devices are accessible and work perfectly well with their original applications (Shelly and Google Home).

I should point out that, after installing the Deco, Home Assistant was no longer accessible with the address http://homeassistant.local. I had to use the IP address of my Home Assistant.

How can I ask HA to start fresh in order to find the new IP.

Tank you !!