I want to send in my apple watch for repair because it won't be charged.

I want to send in my apple watch for repair because it won't be charged. However Apple asks me to remove "find my watch". But I cannot unpair my iphone with apple watch when I cannot even open my watch because it would not be charged. What should I do?

Also, does Apple provides free repair if it is my apple watcher's charger that has a problem? I literally bought it less than a year ago and it is not working all a sudden.