Postal carriers can't read?

So the previous tenant in my apt FINALLY had his mail forwarded somewhere else. YAY, I don't have to deal with it anymore. Well when the regular mail carrier is off, they sub carrier has not clue about forwarding orders. So they deliver the mail no matter what. So I put a nice label on my mailbox. Very clear, very percise...

Deliver mail only for HAYES
Return or forward all others!

I guess the carrier can only read text on US mail since 3 times now, I have gotten the mail for the previous tenant. Wish I could have been here when he delivered so I could have asked him why he decided to ignore my request.