I manged to add the card 2 weeks ago.
Netflix may have changed their payment options. Curve is a mastercard so should work.
Are you putting in the ccv?
And if so what did u do?
Sorted, I think.
After some investigations, turns out the expiry date was wrongly saved. Even though last months payment went through with that date. Inputted new date and card was accepted but I've only been charged 17 cents.