I GM a few games and in a couple of them, I have players that when I reply to their PMs I have to go to the bottom of the PM that I am replying to, and check their name. If I just hit send I get an error telling me that I need to send this PM to someone and to check a name box.

Is this some sort of glitch ?

Yeah, it's a glitch.  I've had it happen to me, too.  Not certain what's happening, but I had to contact a Mod to help get it straightened out.

Somehow I figured that that was going to be my route.

Thanks