Bad service

Am one unhappy customer , I have app**** for a new contract thru mondo and MTN which the approval came from MTN the agent captured my order incorrectly on and MTN wanted to deliver a phone I don't want and now I cannot to another application because MTN and Mondo haven't closed the cancelled order as they refused to amend the initial order , now am struggling to apply for the correct phone I want please help me as it's been almost two weeks requesting this order to be closed and they still have the phone and all the agents I speak to they are not helpful this is the worst service ever from such a big company like MTN no one is helpful