Security Text Does Not Match

I am getting tired of getting this response when I try to send a message. I double check what I type and yet I still get this message. Is this just a random message or is there more to it? Seems like a stupid system but I guess its to eliminate random messages from all the bots that are TN members (which I get anyway). Hmmm, do I have to enter a security to post this bulletin? If so, I know what will happen...