It probably got set to Last Replied by accident or through an update.

“ Milestones” altogether, for those who’d rather not read them again.

But seems available to Star Members only. Bummer.

Phones have very little real estate, so some controls that you see on a tablet or desktop disappear.

No doubt, your cookies got cleared, if they held that preference.

Not knowing where to look for this under My DU, can you log in from something with a large screen and set it the way you like?

That preference should be stored in your browser cookies or your profile on the DU server. (I suspect the latter)

An admin may answer. Good luck.

Settings are a bit of a maze.
Good luck.

with “most recent” there’s a row of black tabs, one of which says “no milestones”.