I want my refund

I am so disappointed with the service received from Toyota Financial Services. When I paid up my vehicle I had an excess amount on my account, and was advised that Toyota will reimburse me. I have been calling in since April requesting for that payment and every time I call I am being told its with the Refund Department and they will get back to me and I never get a call from them. Every week it's the same story and they say they can't put me through to the Refunds Department as there is no contact number. I am fed up because I am the one who is running after them and to think that in my entire life of owning a Toyota I have never missed a payment or had any problems of making payments. It unfair now when I need my money to be treated in this way, surely not buying a Toyota again. Poor customer service