Neverwinter achievements not unlocking

Do you mean achievements? If so then yes you can unlock achievements in Neverwinter

I'm not sure about the hardest. But there was a lot of hard achievements in Neverwinter which I unlocked.

Achievements in that game are really glitchy, it is known to devs that have released an update recently to fix those two, but it is not 100% confirmed yet that it is fine now. Anyway, the issue with that game is that if an achievement doesn't pop when it
is supposed to (the game does not send the notification at all usually), you will have to redo everything with a different char that has not met the achievement requirements yet.

I'll link one of the several discussions on TA for more info on the first one, but it is mostly the same for all the others…

https://www.trueachievements.com/viewcomment.aspx?commentid=1306832

the only solution that I have seen that works is that the game has an update, but unfortunately it is not always the solution as in the case of Gears 5 that many users suffer from that problem

Hey there!

I used to assume Achievement issues were something to do with Microsoft and Xbox because that would totally make sense right! But those issues are with the Developers of the games and in my experience it seems to be a low priority fix for them. Destiny 2 -
about once a Month when I log into the game an Achievement will finally pop up and unlock, Forza Horizon 4 has been weird with that as well, some achievements I get instantly some not for weeks! Sea of Thieves had this issue at launch but the Devs fixed it
pretty fast. I would open a ticket with the Developers of that game and let them know what Achievements aren't unlocking for you