Beware if returning via courier

I have ordered and spent thousands of pounds with next, yet because some of my returns have gone missing since leaving me I'm the one being punished. Absolutely disgusted with how they have treated me! Do they seriously expect me to pay for item's I have returned? So because I have notified them of these reoccurring problem I'm the one being blamed for their warehouse issues!!! This final problem I have experienced with Next is the final straw. There has been so much incompetence from them, they have truly gone too far now. I have been looking into other people's issue's with them and there is a hell of a lot of them. Next is another high street on it's way down. You can't treat customers like this. I have never been so insulted in my life, they have basically called me a liar and a theif!!! You have lost me and all my friends and family as valuable customers now. There sure to loose many more.