Poor service delivery

Afrizone offered me a cellphone contract and promised to deliver the phone that we have agreed on telephonically,but instead they delivered something else,and the monthly installments is now high that the one we have discussed.

I sent my application via MTN and to my surprise afrizone ended up finalizing the deal with low standard performance and when I a m trying to get hold of them to sort out their mess,they are not picking up their phones.

Now I am sitting with single sim phone instead of dual sim phone.