Placing an order shouldn't be so hard

Trying to make a purchase but all I get when I try to add a different payment method is an error message. Tried to use Paypal but even though I have updated my address on HSN and Paypal it will only give the option to send to my old address and wants to charge the full amount even though I applied my Spendableca$h. Sorry, I do not want to use my HSN credit card at this time and should be able to pay by whatever method I want!