Sounds to me like you should invoke your warranty: watch Repair - Official Apple Support
"Apple One-Year Limited Warranty Summary
Apple warrants the included hardware product and accessories against defects in materials and workmanship for one year from the date of original retail purchase. Apple does not warrant against normal wear and tear, nor damage caused by accident or abuse. To obtain service, call Apple or visit an Apple Store or an Apple Authorized Service Provider—available service options are dependent on the country in which service is requested and may be restricted to the original country of sale. Call charges and international shipping charges may apply, depending on the location. Subject to the full terms and detailed information on obtaining service available at www.apple.com/legal/warranty and support.apple.com, if you submit a valid claim under
this warranty, Apple will either repair, replace, or refund your Apple Watch at its own discretion. Warranty benefits are in addition to rights provided under local consumer laws. You may be required to furnish proof of purchase details when making a claim under this warranty."
