Watch will not turn on or charge.
What can I do if my watch doesn’t charge or power up?
Apple Watch Series 3, watchOS 8
Question marked as
Top-ranking reply
Are you using the original charging station and cable that came with the Apple Watch?
If you already tried the troubleshooting mentioned in the article linked above, you should get the watch serviced by Apple or an Authorized Apple Service Provider next to your place:
watch Repair - Official Apple Support