You can receive the reward multiple times for entering a promo code; Increased rewards for applying a promo code. Promo codes are activated in the second tab - Store - Promo Code. List of promo codes: BFEKK BTRGG CAWAM CFFZQ EXGRZ JDWIH NCSYE PBHGF QMPDP SDUGH STANDF UQMRL UUSLY VDGCD YAZVK ZFYBT