Am failing to understand

So I app**** for a cellphone contract with Vodacom for the Samsung S6 Edge, which I got confirmation that it was approved. Shortly after, I received a phone call from the Call Centre agent relaying the same message. Then I was told I do not qualify for the S6 because of my credit score. What I am failing to understand is why was it approved in the first place is I do not qualify for what I app**** for? Please help me understand.