It is important to understand how credit card payments are processed. Initially a payment is 'captured' and then subsequently 'settled'
If the payment is refunded the same day (i.e when the payment is still 'captured' ) it should be in your account the same day. If the payment has been 'settled' then it can take the banking system a few days to return the payment to your account. This can take anywhere between 7 to 10 working days.
Note - this is no reflection on the time it takes us to issue the refund as we issue our instruction immediately, however the banking system moves at it's own pace. Be assured that if we have issued the instruction it is on it's way to you.