This might be something a bit unique, but I was in communication with a GM who said to report it as a bug.
At some point last week, the weekly pinnacle quest “Archives: The First Disc” had been removed from my quest log, without me actually abandoning the quest. It did not appear as an option to pick up a new one this week with reset, but I was still able to collect fragments from last week. Mousing over chests in Delves, for example, would show progress, and opening said chest would grant those fragments up until I cleared 100. However, as the quest itself doesn’t “exist” in my log, it did not progress to a turn in.
GM advice was basically, yes looks like there is a hiccup with your quest. Better luck next week, report it as a bug.
Cheers!