This sounds like the edge case error where the frontend chat UI doesn’t update properly when it’s a “quiet” chat. If you send a message to the chat the UI will draw properly.
Also make sure that channel is all lower case
And your PRIVMSG to a channel where it’s all lower case
so
PRIVMSG #barrycarlyon :Words and stuff
not
PRIVMSG #BarryCarlyon :Words and stuff