If you have one of PRNEWS.IO's vouchers or gift cards, you can redeem them from the dashboard. If you have not created yet account, do it here: https://prnews.io/signup/
After getting access to the dashboard, look for the button Redeem Voucher in the balance menu:
Or you can use this link: https://prnews.io/account/voucher/
Eventually, you'll end up on this page:
After you click Redeem, money promised on a voucher or a gift card will appear on your balance.