Multiple Apple Watch repair rejections by apple internally

In warrantyApple Watch series 11,ios 26.6 facing ecg problem(poor recording).on contacting apple support they done virtual diagnosis and asked me to submit watch at service Center.apple internally rejected repair at service Center.on contacting support they spoke with service Center and asked to raise new repair id but service personnel unable to raise repair id.so support arranged a home courier pickup up and it’s been 15 days courier person not showed up.got to know courier was cancelled by apple internally again.speaking with support senior advisor,sending mails,registering nch grievance but none are helping towards resolution.its been 35 days and diagnosis was also not started and I strongly want a refund and don’t want to wait for repair as there is grave deficiency in service and logistical error.what else can I do more….