Promotional credits are available through our different marketing activities, and they can be used to obtain discounts.
They normally need to meet certain criteria, like order time, order amount, restaurant you are ordering from, etc.
You can save your promo codes in the Rewards section of your account, and read the criteria the order needs to meet for the promo code to be redeemable.
To redeem the code and get promotional credits, simply add it during check out or select it from your Promo codes wallet.