Unsolicited compliments on facebook

I have a public profile on facebook and accept friend requests from fellow ELT professionals I haven’t met if we have mutual friends.

Numerous times this results in exchanges like this one that happened today:

New “friend”: Hi pretty XXXXX ,thanks for accepting my friend request dear
Me (XXXXX): Thank you for the compliment, but I’d rather a stranger didn’t send me a message calling me pretty. Thank you for understanding.
New “friend”: Yeah am sorry my friend but your picture shows your beauty. Am like how has been your day
Now you may be thinking, come on, all he did was call you pretty.  But this is only one example. And this happened immediately after I shared the ELTtoo website!
Maybe this is just a nice guy giving me a genuine compliment and had no intention of offending me. I hope so. And if he is now upset by my reply, that’s too bad – but something I have to do now as experience tells me that if I don’t nip it in the bud, these kinds of messages end up with the new “friend” sending me countless messages and not leaving me alone. For some people ignoring doesn’t work. Asking politely doesn’t work.