GERO SOUND - I PAY AND NEVER RECEIVE!!!

I have a music school and my students wanted some new backtracks. So I saw this advert on Facebook and have a long discussion with this guy. I confirm all the backtracks I wanted to order with him and make the payment into his bank account. I have ordered 20 backtracks and only received two backtracks until today. Everyday I ask him and he said he will send them. But until today I haven't receive anything. It is also the parents who pay for the tracks and now I must explain to them... Please help!