Ola — Not refunding my money

On 21st aug i booked cab which the bill was coming around 400 rs.while reaching to destination it came 800 rs. I raised complain which was recognised on 9th sept. They told to share bank details which I shared. Still till now, I didnt get my refund. I called 20 times to customer care but they are not resolving my issue. Every time they are asking for crn number and ticket number which i provide but no response.
This is the case of customer care and i am fedup with this.