How can I pay the state efile fee

I am using the Premier version of TurboTax on my PC in order to prepare the taxes.  I have added my credit card info to my Intuit account.  I successfully efiled my son's federal return however when I try to efile my son's Mississippi return it will not go through and says I must call customer service.  I've been on the line with customer service for over a half hour and they have no idea how to pay for the efile.  How can I pay for the state efile fee and efile the Mississippi return?