Prevent multiple users from editing the same list item at the same time

I have a list on SharePoint Online, where I need to make sure that only one person can edit a list item at a time. For example, if Person A edits a list item, it MUST be clear to everyone else working, that Person A is working on this list item and no one else should be able to edit this item.

As this is a list I am unable to turn the check in/check out feature on like I could if it was a document library.

Any suggestions would be much appreciated.