Incorrect title for a game on Steam

Something like that happened to me where my L4D2 turned into TF2 for some weird reason and I had two TF2 in my account, but I've never head it happening to things other then valve games. Could be something similar though?

According to steam support it is because you have the game installed multiple times. This apparently messes up the config file. I don't entirely believe this is the cause but that's what they said back when the L4D2 is TF2 thing happened.

Valve is crazy

i had same shit with my portal that became HL2:E1

from the one hand its good, cuz i dont have it. but from the other hand, its not leting me to play it nor portal

I don't know if this helps but when I had the problem I had to do this to fix it

Steam://flushconfig

Taken from here

Which worked fine for me, but I have no idea if that will break, destroy, become sentient or create artifical intelligence on your computer so try at your own risk I guess?