Currys PC World

I have discovered that i have been getting £5.99 a month taken out of my account with no way of cancelling it through my bank for "product support AG" and I don't know exactly when this started,I haven't got a clue what this is and I do not remember agreeing to this. I never ever take out any kind of cover on any purchases. Could I please have this cancelled immediately and the money owed returned to me ASAP. I first contacted you in May 2019 and had a response back on the 24th May 2019 stated that you had received my enquiry and that it would be dealt with shortly. Since then despite contacting you another 4 times I still have had NO RESPONSE and you are still continuing to take my money without my consent.