Sending back a sim card.

I had trouble getting onto chat when I was due an upgrade on two phones, one for me and one for my husband. I was eventually told to go to Carphone warehouse.  After driving 30 miles and waiting 1.5hours they could not help.  I went on line and took out a monthly contract on two sims on 4th August. I then realised that this was probrably a mistake as the other two phone contracts would continue, fortunately I managed to speak to a very helpful lady and she sorted me out with two sim upgrades.  She said to wait until the other sims arrived and cancel these on chat.  I managed to do this after several hours on 5th.  I then cancelled the direct debits.  I yesterday received a confirmation of the set up of the Direct debit and I am told that I insured charges for the time we had them!!! The morning they were delivered they were cancelled.