i bought a game time card 30-day throngh paybycash(i use ultimate game card buy VIP),I want to use the game time card became vip so i click "upgrade now!"and select "Game Card or Other Payment Methods" then i input the code click submit after i saw "Order Summary" the system said "Please review the information on this page and click "Place My Order" to complete your purchase." so i click "I agree to the Game Purchase Terms & Conditions, Subscription Terms & Conditions, Terms of Service and Privacy Policy. I also agree to pay the maximum sales tax applicable to a resident of my state. All state and local taxes are non-refundable. " then i click "place my order" but i find a error:PROCESS_BUY_NOW_UNABLE_T O_FETCH_PRODUCT_KEY .why? how to fix the error? i am a free player and have not used any cdk the game time card is my first buy !