Groups are automatically created at the time that the event is created. If you copied over an old event, the group name would reflect the name of the copied event. If you changed the name of the event after copying, this edit does not effect the group name. It would be wise to make edits to the group name to avoid any confusion in the future:
  1. Navigate to Constituent 360 > Groups.
  2. Search for the copied event group name.
  3. Select edit next to the group.
  4. Make the neccesary changes to the group name and save.