KitchenAid well and truly mixes up its customer service

It told me my stand mixer repair would be free … then I got a bill for £134I have a KitchenAid Artisan stand mixer, purchased in December 2011 and which came with a five-year warranty. In January 2016 it was repaired under warranty when the speed control lever no longer functioned properly, but a year later it developed the same fault. KitchenAid advised that it could be repaired for £70 plus parts. At the end of March, after weeks of unanswered emails, I got through to Kitche