Recently, I tried to participate in a group chat that the group's creator posted a link to in the Discussion area of a Workshop item. At first, the link seemed to work for me. But when I tried to send a message to the group creator, I got this error...

"You have been sending too many messages in a short period of time. Please wait and try again later."

I got this error twice, once when I tried sending a message through the "Open in Web Chat" link and again when I gave that up and tried sending a message through "Open in Steam" (Steam Client chat) link.

What is strange is the fact that I had not sent any other messages through Steam chat that day - or any in the last 12 months or more.

I do realize that if we try to send too many chat messages in a short period of time, then some sort of spam filter will activate and give that error. But, clearly, that was not the situation in my case. So... what's going on?