poor service

I have settled my loan. and i cannot understand what it is that is delaying the refund of that over payment. when i contact them, i am advised that the refund will done in 3 workings, those days went by, and i called again, and i am told it actually is 3 to 5 working day. that too went by, and i told now it is up to 7 working days, of which today is the 7th day, and i am still waiting. if i was delaying in repayments i would be black listed immediately.