SSDA ******** AND BULLIES OF NOTE

I have been trying to help my sister to get information about an alleged amount she owes for and unpaid Avon account. She has never ever had an Avon account and this is the first she has heard of this. They refuse to give her any information unless she provides them with her id number which she refuses to do. They then put the phone down. She was threatened with being black listed. They will not give her any statements or proof of purchases or exact amount due.. They phone her and then demand to have all her information EG I.D. address etc before they can supposedly assist her. THIS IS A **** TO GET INFORMATION OUT OF HER. Can they be reported to the law society or the consumer protector?