Vehicle Finance

I made a payment arrangement for last week Monday, but unfortunately I couldn't honour it, due to the fact that the money that I was waiting for, as i'm currently unemployed since 2013, only came through later, and only managed to pay the amount on Saturday. But on the Friday I received an sms from John, from your legal dept. saying that I must make contact with him before end of business on that Friday 04/12/2015, OR pay the arrear amount of R15903, he even sent me a whatsapp msg, of which I rep**** to him before end of business. But this morning a get a call from him that I must pay the outstanding amount of 10903, or you'll reposess the car, I even asked him to give me atleast until Friday to make another payment of 5000, as ive been paying this amount for the past 3 months and communicating with Junior, to cover my arrears but I was told that there's nothing he can do, whats the point of making arrangements if you are not will to help me. What is the process of repossession, as I feel like what you are doing is *******, as I never received any formal notification i.e final demands, or court order only those sms and whatsapp from Friday.