Speedmaster reserve

There's certainly something wrong with your watch if 14 hours after winding, to a hard stop, it doesn't run anymore.

It's under warranty, take it into an AD or better still Boutique ASAP. Or if you prefer contact your local service centre directly. It's prob a broken mainspring but whatever, they will do a full movement service (but no cosmetic work) and you'll get it back working fine with a 2 year warranty extension from that point, ie it will then be covered until ~August 2026. Here in the UK at least they prioritise warranty servicing over regular paid for, and you can get a watch back in less than a month in my recent experience. I can't speak for your location however.