When working in Google Maps, a frustrating issue occurred, concerning lists, list editing, and list deletion (rather, the inability to delete a list). Part of this is resolved. I found that the list which has the issues was automatically created in and added to my Google Maps app by a different app, as part of an event I created.
Here's what happened. In my Google Calendar app, I added an event reminder. The reminder has an option to add a location and link a Google Map to the event reminder. Then it allowed me to save that map. When I hit 'Save,' the options included saving to an existing list, or creating a new list.
I created the new list, 'June Trip'. I didn't realize it then, but the list I saved in my calendar was saved to a different app--my Google Maps app. Later, when I opened Google Maps and viewed 'My Places', the list was there. Trouble is, I couldn't edit or delete the list or the map, and at that point, I couldn't remember how I added it! (I tried every option in Google Maps and in the map view itself; editing was not an option). At that moment, the June Trip list, with only one map point on it, seemed useless, but I could not delete it. Frustrating!
However, I later discovered that I could go to my Google Calendar app, look up all reminders relating to my June trip, add a location, link a map, and 'save' the location to the aforementioned existing list in Google Maps. Nice!
This accomplished what I was trying, but unable, to do straight from the Google Maps app. I guess part of the confusion is that any location list that I create in my calendar app automatically saves into my Google Maps app. So, I open Google Maps app, go to My Places, and see the list in that menu, but the list cannot be edited from there (interesting, odd; don't know why).
Anyway, I presume the list will be deleted from Google Maps when I delete all related reminders (group of related events for my trip) in the calendar app. All is well, if I can just remember all this after the trip! 🤔🙂