Trying to customize the Chat float button

Trying to customize the Chat float button

Trying to customize the chat float button so when no one is online it doesn't say:

"Leave a message"
"Leave us a message"

as it currently does.

But when I go to change the button appearance and change the  First line text to something else, when I save it I get:

Error occurred while processing your request. Please try again later!

Well, it's later and this doesn't seem to be magically fixed.