in some countries one always have a 14 days return option full refund
warranty is only valid in the country where one purchases a product
these forums are user helping other users like yourself, it's sort of going
to a physical apple store and asking other customers their advice
so if you wish to reach out directly to their support channels you can try
Get Support (apple.com)
And or
Contact - Official Apple Support
And or
Contact - How to Contact Us - Apple
Or
Genius Bar Reservation and Apple Support Options - Apple
otherwise I suppose you can always just buy a band
Buy Apple Watch Bands - Apple