How to get my money back

Hello Sir/Madam, I was booked a ticket from Madurai to Chennai on 04-Sep-2018 by 11:53 PM via RedBus. The scheduled time for the bus to departure is 05-Sep-2018 00:30 AM. I was there in the boarding point by 05-Sep-2018 00:10 AM. But the bus was departure before the scheduled time without any notification. I think it was departure before 12 o'clock. I enquired about this to the person who in charge for Orange Travels, Mattuthavani, Madurai. His answer is not acceptable and he promised to board me on another bus in same travels. I waited until 01:00 AM. Finally he said the driver is refused to come. And i used another bus from Sri Krishna Travels to arrive Chennai. It is terrible to stand during mid-night at bus-stand. I raised a complaint about this in Chennai office via phone immediately next day. They said my money will be refunded within 4-5 working days. But still i am not getting any refund. And I sent a complaint mail 3 days back. Still no reply for that mail also. Can someone please help me to get my money back.?(Is it possible to register a case against the orange travels?) Thanks in advance.