Not sure if anyone has done this but my son took out a Barclaycard a few years back. Recently I noticed he was paying quite a lot for his S&R cover yet he had no knowledge of ever agreeing to take it out.
I got a letter from the web and wrote off for him. 2 months later he has received a refund of £860.00. Evidently it is up to them to prove it was sold correctly which in this case they could not as they had no written evidence that he agreed to take it out.
If anyone is interested I can let them have a copy of the letter he sent. You never know ......