Since last update of Gear S3 it seems that every time you try to set/send a Watxhmaker face to watch, it just "exits" and sets a Samsung watchface. Tried all of the usual tactics, rebooting, changing faces and whatnot.
This was caused by a Samsung not a WatchMaker update. We have submitted a fixed version to Samsung (29th August) and are waiting for Samsung to approve this. This usually takes a week but I have requested a faster review.