Your rights are limited. Who did you purchase the Watch from? Apple Watch Series 6 was introduced in September 2020 and discontinued in September 2021. Apple’s standard warranty is a basic 1 year warranty that covers manufacture defects in materials and workmanship. Apple Care can extend the basic warranty when purchased within the specified time frame.
Since Apple Care is not in effect, I’d suggest you return the item to Apple and get a diagnosis and make a determination on the issue and serviceability of the watch. If it’s actually water damaged, the watch is probably beyond economical repair.
I would also note that Rolex’s don't guarantee waterproofness. Rolex, just like Apple guarantees, water resistance, not waterproofness. Rolex’s warranty is for 5 years. Apple’s is for 1 year unless Apple Care is purchased. Least expensive Rolex, Oyster Perpetual, is abut $7,000 in the US.
My point? The $6,500 difference buys a lot of Apple Watches or Apple Care or even both.
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