You can’t do anything if your opponent disabled the chat. Players can disable all chat in their chess.com settings; your next swiss game should have the chat working again if the opponent has chat enabled.
Some players just prefer chat disabled, so they can focus on the chess; I wouldn’t be surprised if this was the case for a tournament although chat on or not is a personal decision.
I am in my first tournament and I have a question but the chat dialogue box says "chat disabled". how do I enable it?
BTW- I am in a swiss tournament and was wondering when my next game starts or do I have to do something (like is there a lobby?)?
thanks,
John