Abstract: A method comprising automatically assigning cryptographic tokens to cryptocurrency wallet addresses via a smart contract hosted on and executed by decentralised virtual machines of a decentralised network, storing received transaction history data in a transaction database; analysing and matching purchase transactions in the stored transaction history data by calculating a matching accuracy score; applying a predetermined reward rule on matching purchase transactions that have a calculated matching accuracy score above a predetermined matching threshold; wherein the predetermined reward rule comprising: calculating an amount of cryptographic tokens to be assigned at least based on an amount of the matching purchase transaction; and assigning the calculated amount of cryptographic tokens to a cryptocurrency wallet address of a user via a blockchain transaction by digitally signing the blockchain transaction with a private key.