Vodacom declined contract for no valid reason

I wanted to take a contract with vodacom, i called the contact centre and was declined, and the reason i was given was because of my credit status, i then called they affiliated credit bureau trans union and queried the reason i was declined and they told me there is there no valid reason they should not have declined me. i called vodacom back and i asked for a valid reason, all they could tell me was that i didnt meet the credit criteria, when i asked what the criteria actually is, the call centre agent said she doesn't know the criteria, so in essence vodacom declined me because of their credit criteria which their own staff are not aware off, so how accurate/valid the outcome of my application is? i app**** for the contract through MTN and i was approved and received excellent service. Vodacom should train their staff on their own policies and criteria's before they attempt to assist clients.