Can't get the 900 points reward from gamekit??? So if I haven't completed any previous tasks before quest 6 I can't do the quest?

Can't get the 900 points reward from gamekit??? Quest 6 and it's about purchasing premium currency worth 4dollar or more and that option is available on gamekit store for 900points. When I tried to redeem the reward it came back to me as rejected by the reason "no task completed"?