Annoying chat message box

Hi guys , i have this annoying problem with this pop - up window asking about a password (?) for a chat group
I'll leave a screenshoot for better clearness
I don't think is an addon problem , it will persist even when i deactivate all my addons

P.s: I use a client from another server , maybe is this the problem ?

https://ibb.co/XxcJRPP

It's Carbonite addon. It's trying to join a channel but someone has set a password for it. If it's still there after disabling addons, the channel might have been added in Social > Chat. You can remove it there. In Carbonite settings you can disable joining chat channels.