It's really unfair of you to not wanna put consumer needs first honestly

So I honestly received great service at game store in Rosebank my problem is I'm struggling to return a device that I haven't used and it's only a day that I bought it due to the fact that it's not compatible with the app my daughter has to use for their studies as far as it goes the cooling off period is supposed to be 7 days hence why I don't understand why I can't get a refund on it..... I will definitely pursue this matter further because this is taking advantage of customers