My PHB says :''Other creatures don’t gain advantage on attack rolls against you as a result of being hidden from you.'' That's why i said that. Is it a ninja errata to Alert because i don't see it in the PHB Errata https://media.wizards.com/2015/downloads/dnd/Errata_PH.pdf''
I see said the blind man. Which if I had the alert feat would mean that my attackers would not get advantage on their attack!

Yeah, I use DndBeyond for rules because it's always up-to-date. That and I'm lazy.