Only card manufacturer will be able to help you regarding all connection problems, not limited to the following: 1) call failure 2) over deduction of credit balance 3) call interruption 4) poor voice quality. For these issues, contact customer service of the card manufacturer, which can be found on card information on our website. Sometimes you will be asked to provide serial number and other card information. You can contact us for these and we will be ready to help you. On the ground of confidentiality of the data, normally card manufacturer would like to talk to end customer directly. We are not obliged to help you on this case. Select your card prudently based on your experience. Also we do not refund for these problems as well. See our Refund Policy.