Apple Watch Series 7
My watch has trouble charging I have only had it since the 01 November and had to reset it every other day to get it to charge
Apple Watch Series 7, watchOS 8
Question marked as
You need to contact Apple Support without delay, and get a ticket opened. If you are going to reject a defective device you bneed to get your claim in before day 14.
Remember there is a 14 day return window, within that you should get either a refund or if they swap out the replacement should be another brand new device. After 14 days you are in the lottery which might bring a reconditioned replacement.