Oookay, that is weird!
I don't know what those tabs at the top are supposed to be. Maybe groups, sources or categories of contacts? It's presumably a feature of the Samsung contacts app, but my only Samsung device doesn't have that.
Ah, I see that while I've been typing this you've answered the next question I had: did you do anything around the time this started?
All I can think of is editing manually. That's not too hard with contacts synced with Google (you can use a computer rather than the phone), but I'm guessing these are things that were only stored on the device? I don't know whether removing all of the contacts from one "device" will cause that category to disappear as well.
I'm also guessing you don't have a backup from before you did this sync (as then you could just clear everything and restore from the backup).