online shopping fails

I am trying to buy an Item from take alot.com everytime I click on do payment It asks for my cvv number when enter it I get my otp pin when enter that each time it rejects my paymeant...WHAT DO I DO.. I CALLED FNB BANK THEY PUT ME THRW TO ONLINE BANKING ONLINE BANKING PUTS ME BACK TO GENREAL BANKING...SICK&TIRED...IS IT TAKE ALOT.COM OR IS IT FNB???COME ON