It turned out on closer inspection of my final bill that I had been charged £49.99 for mats that I had neither asked for or been told about. I also had said no thank you, to the £15 child sponsor offer but had been charged for it. I was told by the store manager that because of the deal that we had struck with my trade in, they had to recoup that cash somehow !!! I couldn't believe what I was hearing, I was so angry at this point , out of principle that I settled my bill and left. It was only when the customer services manager called me to go through my purchase that everything was sorted out & I was reimbursed the £65. Thank you Claire.