Starred items losing their place

[Wol Gilbraith]

Each night I Star what I’m going to do tomorrow, and the next day I un-Star them as I check them off. When they recur, or if they are deferred, I Star them again, and so on.

On my old PC (Windows 10, MLO 5.1.4), Starred items would take their place in the starred list just where I placed them the previous time

I got a new PC about 2 months ago (Windows 11, still MLO 5.1.4), and now many of my Starred items keep appearing at the *bottom* of the Starred list, time after time. Not all of them, but many. 

It’s driving me daft. Does anyone have an explanation, or, better still, a solution?