Upfront payment not credited on cancellation.

In June I was advised that I could upgrade my phone early. I choose a phone on the ID website and it was delivered the following day, I made an upfront payment of £29.99. On receipt of the phone I realised that I had made a mistake and purchased a phone on a brand new contract. I contacted Customer Services straight away and arrangements were made to return the phone. Customer Services confirmed receipt of the phone and I received notification that £1.26 will be taken from my bank via DD [final bill for a phone I did not use?]. That aside, I have been waiting for the up front payment of £29.99 to be refunded. I called Customer Services on 9th July. I was told that Carphone Warehouse would credit the amount and was transferred to them who stated that they would not credit the amount and I was then transferred back to ID Customer Services. I was then told I had to go to a Carphone Warehouse shop to get the credit arranged……..I refused as the contract was arranged online via ID. I was then told my credit card would be credited within 3-5days. THIS HAS NOT OCCURRED. I would be be grateful if you would let me know when I can expect to be refunded. Account No.[removed], mobile No.[removed]