Apple Watch series 3

Hello, my Apple Watch Series 3 is not charging. I sent for repairs under warranty, they did not fix anything, they just returned it back, saying that everything is fine. The second time I sent it to the service center for diagnostics, they also returned it a month later, saying that they did not find any errors. As a result, the watch still does not work, does not charge. The warranty expired while the watch was being diagnosed. Please see my message and help me with this problem.