Disclosure of confidential information

In October 2017 I was in contact with Lawrence from Naboom Toyota applying for Mercedes Benz C180 and he told it was approved. A week later I tried to call him to ask when is the car being delivered and he told me he was in Cape Town to celebrate his child's birthday,but will deliver the car as soon as he comes back and he confirmed that will be on a Tuesday. As I was referred to him by my sister in law,she then called me to say that my application was declined due to my credit status and she mentioned Edcon of which I know that I did not pay it for several months as I was not working. I then called Lawarence again to ask him about the matter and he assured me that he did not say anything and my car is approved he is going to deliver it when he comes back from Cape Town.To date I have not received my car and I feel so embarrassed as my sister in law now knows my credit status and I feel he did not keep to his promises of delivering the car and again disclosing of my confidential information.