Customer services (if there is such thing) are useless. For a few years now the same man has been messaging me. I told him from the start that I wasn't interested. I block him but it's not permanent and he's able to message again. I block after every message as I don't want to be giving him attention by messaging back. I can't change my name as I'm not an upgraded member 
and I don't want to hide my profile.
What can I do?