You receive ATLAS Credit when someone creates an account using your referral code. This means that if a Client of yours does not have an ATLAS account, and he/she creates one using your referral code, then you will get ATLAS credit. You can also share your referral code with people that want to become a Specialist and create an account on ATLAS.
Your Clients or acquaintances/friends that already have an ATLAS account can’t add your referral code to their account. You can only add the referral code upon creating an account.
Don't know how the Referral System works? Find out more here.
Note: Learn more about ATLAS Credit here.