Accepting credit cards through your merchant gateway

[sneakervore15]

Under site preferences my account is active to accept credit cards payments from buyers but i still get errors whenever i try to list an item and i want to accept credit cards. My payment gateway is authorize.net, I know everything is ok on their end becaue the test charge eBay implements during set up went through successfully. I've called and emailed customer service and so far no one has found a solution. Does anyone know of a specific agent i can speak to that has expertise in this area? Any help would be appreciated thanks.