I'm having the same battle with them over PPI - they are very stubborn.
If you opened your account in store you probably had the same form as me & the OH, there is NOWHERE to sign for ppi or even a 'tick' box consenting to ppi.
Just received my cca (bad copy) from CL - after Santander stating they no longer have it due to the age of the account, in very small print at the bottom its stated that ppi will be added free for 28 days - its up to you to cancel within that time if you dont want it (complete rubbish - IMHO!)
If you'd like the exact wording I'll happy quote the paragragh on your thread.
With compound
interest
mine stands at well over £9k.
I cant find any success stories concerning Debenhams ppi - hoping mine may be amongst the first
Beachy