Sharepoint List: Item No. and ID

[mike_302]

I designed a Sharepoint List (using Lists app, but I don't think that matters -- I'm working in the Sharepoint List in Sharepoint itself now).

I want every entry to have a unique ID. I know there's the baked-in ID column.

There's also an "Item No." column I can't seem to get rid of. Every new entry requires a user to input an Item No. but I don't want that. I'm (semi-)happy with the ID column on its own. (I'd really prefer a column formatted like "xxx-###", but that seems like it requires a lot of programming to implement)

I can Hide the Item No. column, but that doesn't exclude it from the New Entry form as a Required input.

The only thing I can think of is that the Item No. column is "Linked to Item with edit menu" - maybe I can't get rid of columns like that? Maybe I have to reassign that property? But reassigning that property seems like a disproportionately difficult action requiring SharePoint designer or JSON code (from blogs I've found). This can't require such an effort... How many Lists do people put together where they don't want the user to have to input an "Item No."? 

[#2]

@mike_302 Item No. Would be a custom column on your list. If it's not being used and you don't need it anymore. You can go to the list settings page of your list, and remove the column all together.

[#3]

@Beau Cameron  Thanks for your response

So I go into List Settings, and in the Columns section of the page, most of the columns are listed. However, Item No. is DEFINITELY not listed. It does seem odd, but I'm 100% certain. What reason might this be? "ID" is also not listed.

[#4]

Is this form customized in your environment? Also ID is an internal column, not something you can change, so it's not shown. 

[#5]

I don't know how to evaluate if it's a customized form. It's a Sharepoint site created from a recently created Microsoft Team; and the "form" (the List?) was created by the Microsoft Lists app. Perhaps the Lists app has created the Item No. column as an internal column? Unsure :S

[#6]

@mike_302 I haven't seen a List from Lists app with that column. It's a bit hard to say, can you take a screen shot of your settings for the list columns?

[#7]

@Beau Cameron attached

[#8]

@mike_302 Did you ever get an answer for something related to LIST ID: XXX as that I what "I" would like as well!  We have an ID column that every list in SharePoint has, but having it listed with "text" is helpful.  I might have misunderstood your message, just thought I read that you wanted something like that.