Unacceptable service

I find it totally unacceptable that I need to go through the complicated process of returning items that you decided to duplicate on my order. I do not and will not be going to the shops to hand a parcel in and still pay for the return that you stuffed up on. I expect an urgent response to my query with a resolution that does not inconvenience me. I have been with Avon for years and find the completely unacceptable. Please resolve urgently.