Miele Sold Me a Stick Vacuum That Refuses to Clean Any Type of Rug

The Miele stick vacuum I purchased hasn’t vacuumed my rug properly since the first use. The brush on the head doesn't rotate at all. When I requested a return, they rejected it by saying the vacuum functions properly—it just doesn’t vacuum my rug. However, they never warned me beforehand that it might not work on certain rugs. After I filed a complaint, they asked, “Is your rug too thick?” and claimed the vacuum doesn’t work well on thick rugs. But my rug is actually thin. So this vacuum seems picky—it doesn't work on thick rugs or thin ones. I’m deeply disappointed, especially since I trusted the brand. They refused to accept the return for a vacuum that can’t even clean the only rug I use. I’m truly upset.