Circle Mask visible in Timeline but not in Layers List

Hello to the Experts!

Here I am with what I feel is such a remedial question - and even though I am a member of a couple of Patreon groups now, I feel most comfortable coming to you all here instead. :)

I'm not sure why or how (or what I did) to change this, because the Masks always used to show in both in the Layers Panel and in the Timeline. Now I only see it in the Timeline...and it's driving me crazy. What do I need to turn back on in order to have the Mask show as it's own Layer in the Layers Panel?

Thank you as always for your time - you know I appreciate you guys!