Thank you for your question. Upwork accepts Visa, Discover, Mastercard, and American Express debit cards. We do not accept virtual cards or gift cards. Prepaid cards may be used to purchase Connects, but not membership plans. To learn more about adding a debit card to your account, click here.
I hope this helps!
Please know that in order to add someone else's billing method to your account, the owner of the billing method needs to authorize you to use it. Please contact the card-issuing bank for more information about the specific charge decline. You can also check out this help article for more information about available Billing Methods that might work for you.