Intercity withholding my refund

I have requested a refund for my bus ticket 3 months ago, I have called almost every week, sent so many email, given my bank account details 4 times. Still intercity is not refunding my money. Their policy states that refunds are processed with 21- 30 working days. But here I am 3 months later they don't want to refund my money. Can someone please advise me what do