Xiaomi Vacuum Battery Woes and Customer Service Runaround

My Xiaomi cordless vacuum, which is still under warranty, has a problem: the battery is dead, rendering it useless. When I contacted Xiaomi's customer service, they referred me to Genpa Dora, the Turkish distributor. The plot thickens, however, with the inclusion of Evofone. They asked me to find out where I got it from so they could 'help.' After speaking with Genpa and Dora, they both deny any involvement, claiming that the serial and email numbers (serial no: 28829/00003967) do not correspond to their records. Despite the fact that my product is still under warranty, West Bilisim, the seller, claims that they do not have batteries in stock and that replacements are shipped from China. They've been dragging me along, claiming that there are six others in line ahead of me. I'm frustrated as I try to repair my still-covered device. I urgently need help to get through this ordeal. (Telephone: 05394****)