I am sorry the service has not met the quality you expected us to offer. I have understood your request for canceling the order. I will refund you after I have e-mailed you this time, so please confirm that.
I apologize that I am unable to perform the service that you expected. I understand about the cancellation. I will refund you after this email so please confirm it.
I am sorry for not being able to provide any service which meets your expectations. I noted your cancellation request. I will issue a refund after sending this e-mail to you. PI would appreciate if you can confirm.