Recent E-mail about pro-rated refund

I just received an e-mail from Norton regarding an upgrade they are going to do on the anti virus subscriptions.  They offered either a reduced rate on renewing, or a pro rated refund on the existing program.  I went through the motions of getting the refund and came to a page that required a lot of information I am unwilling to give, such as:  Bank Routing number, Bank Account Number, City, State and Country of Bank.  Since the e-mail eluded to the fact that a refund would be given back to the same method used when I purchased it, I know Norton already has my Credit Card information on file.  I "chatted" with a Norton representative who kept telling me that all I had to do was put my credit card information in the line where it said Bank Routing/Account number.  After several attempts to do that, and after her insisting that this was all fine I just logged off.  I will not put this personal information out there, when Norton is already the proud owner of my Credit Card information.  I just wondered if anyone else has dealt with this and what is the correct thing to do?