Why won’t my new Apple Watch turn on although it has been charging for 6 hours
Why won’t my new, unboxed Apple Watch turn on although it has been charging for 6+ hours
If new but unboxed I would be prepared to contact the seller urgently for refund,
If the Apple Watch is not responding,I suggest performing a force restart. Steps needed are found in the Apple Support article: Restart your Apple Watch - Apple Support
Which also contains instructions to force restart your Apple Watch,
i.e. press and hold both the side button and Digital Crown for at least 10 seconds, then release both buttons when you see the Apple logo.