iadxb
278
Wish you posted here before parting with this special watch
In my experience with several UN watches, including GMT +/- Perpetual, Sonata, and Marine Chronometer, I can confidently say that automatic winding was not very efficient (no idea if UN made any improvements in this regard, I have experience with 15+ years old models that were using modified ETA movements as base).
I too found that out when my perpetual just stopped on day 3 or 4, and later I could clearly observe this in the Marine Chronometer (due to it having a power reserve indicator) that the power reserve will gradually decline over days with normal wear.
It surely varies from person to person as some of us are more active than others, but from winding efficiency point of view, my UN watches were clearly underperforming when compared to my other automatic watches.
This never really bothered me, as solution is simple: you can keep it on a winder overnight, or simply manually top it up every 2-3 days.
I hope you will soon reunite with your watch or find another similar one!