Debit Card Invalid

I opened my Seller Central Account approximately two weeks ago. However, my TD Bank debit card, which is internationally chargeable and valid, is shown as invalid. I started seeing this error a day after Amazon charged me its monthly fee for a Professional Account, a plan I did not even sign up for. I also called my bank to check for any restrictions it may have possibly placed, but it turns out that the card is operational for every type of transaction. I even scheduled a call with customer support with the Amazon team last week twice, but unfortunately, no one called me back and my case was solved automatically. I even emailed a customer rep. who instead of helping me solve the issue kept showing me the reasons why my card might be invalid.

This afternoon, I also changed my debit card, and once again, I am seeing the same error. I am extremely disappointed with the service I am receiving from Amazon Seller Central's help desk so far. I already have an itinerary waiting to be sold. Once again, both of my debit cards are VISA cards, and are valid and compatible for international transactions as well. I would really like to talk to someone from Amazon Seller Central to solve this issue. I have been reading similar forums on Seller Central of this being a possible systemwide issue. But in any case, I need a refund and an explanation on how Amazon automatically signed me up for a Professional Plan than the Individual one which I selected, and why both of my debit cards despite being VAID AND OPERATIONAL, are not working on my Seller Central Account. If this issue is not solved within a month, then unfortunately I will have no other option than to look for alternatives to Seller Central. I hope someone from Seller Central will take note of my concerns and get me connected to a knowledgeable representative who actually has experience solving similar issues.