Upset and angry with addidas

I bought my son a sneaker on the 27 November on the adiddas app, This was the first time using the app and they had a promotion on the shoe that my son wanted. Im a mother of 3 and work in retail so i try my best to provide my kids with what i can afford I have still not received my order and i tried numerous time to call and email but im not getting any answers, my order said it would be delivered on the 30th then there was a massage to say they have a delay. My son is leaving for the December holidays tomorrow and he will be the only one out of the 3 kids wont have a sneaker Please help me to get some answe