Completed prerequisites for the achievement Memories Buried in Time and didn't get it

Perhaps you'll have to give it a little time. It should unlock itself.

Have you tried follow the steps here?
https://forums.xbox.com/en-SG/thread/8a46e4e2-6891-480a-873b-afb962a99642

I phoned in today and talked to a different analyst who was very helpful. We spent just over 2 hours troubleshooting the issue. we've exhausted all troubleshooting steps including a factory reset on the console and transferring my saved game to my xbox 360
console to see if it would pop up there but it didn't. We verified my achievements through the trueachievements website and I definitely met the prerequisites to the achievements. They are not showing up on trueachievements either. Some of the achievements
are obtained by completing certain quests for example. The quests are showing completed in game, but the achievement (although it did pop up when I completed the quest) is not showing up in my achievements

Mike (Rebellion Developments Ltd.)

Feb 5, 12:57

Thanks for contacting us.

There are certain things that might prevent you from collecting achievements, which are 1. Joining a game already in progress will prevent you unlocking level completion related achievements, and 2. Joining a game after collectibles have been picked up will
prevent you getting collectible related achievements.

In this case it seems that you got all the prerequisites but the Xbox didn't get a chance to or didn't properly manage to communicate it all to the Microsoft servers. As such I don't think there's anything we can suggest on our end of things. The problem
is between your Xbox and Microsoft.

I apologise for the inconvenience.

Regards,

Mike

Still waiting on 2 achievements from The Book of Unwritten Tales 2 from Xbox Games Pass. It has been about a week... the achievements in question are not missable (unlocked through normal progression through the game, were prerequisites to achievements
that were unlocked normally) and I was online at the time of completing the requirements. Is waiting over a week for achievements to finally unlock something I can expect from games I play using the Games Pass?