Karcher VC6 Vacuum Battery Issue - Poor Service and No Response After Sending to Repair

I bought the Karcher VC6 stick vacuum in November, and within just 6-7 months, the battery stopped charging. Even the cheapest brands made in the Far East don’t fail this quickly, but the Karcher battery broke down, and I had to stop using the vacuum. I contacted Karcher service, but reaching them was a nightmare—I waited on hold for 25-30 minutes on the phone. Eventually, I sent the vacuum to the Halkalı service center, thinking the worst was over, but a bigger issue began: the post-sale support. The service received my product, and days passed—3, 5, 10, 15—without any calls, emails, or SMS updates. I called them, waited another 30 minutes on hold to speak with a representative, who told me it would take 20 days, which I accepted. But now, even after 20 days, still no updates. I’m at a loss about what to do next. How will my problem be resolved? Was trusting Karcher a mistake? Karcher, I need proper communication and a solution to fix this!