Well, I decided to look into this after I was told that I have PPI on my shopping catalogue.
So I sent a SAR request, which they provided within 7 days, I works out that I had paid over £600 in PPI, and that I was paying a third towards PPI per month.
SO I decided to request this back, and for them to stop the PPI.
I received a reply within 2 weeks, which both requests have been refused.
I had a woman phone me, who asked to speak to me, and I was busy but I requested that she dealt with this via letter, because I wasn't recording the conversation. She then told me, that she would decide whether to deal with this or not, based on the fact that I had refused to speak to her.
As dx has already suggested if your catclogue company have given you a final response which states they are not willing to refund you then you can refer your case to the Financial Ombudsman Service (fos).
This is a free service to you and an adjudicator will look at your case and decide whether they were right or not to refuse your claim.