Goibibo.com has cheated me by taking payment for a return journey, but has issued ticket for one side only

I & two of my family members want to travel from Kolkata to Tezpur & back with journey dates 9th april, 2016 & return journey date 16th april, 2016. I searched all travel sites & found Goibibo.com website giving the best deal at Rs. 15,864/- Other sites namely easemytrip, yatra.com & expedia were selling the same package at a higher price ranging from Rs.17000/- to Rs.18000/- Hence I decided to book through Goibibo website on 9.3.2016. After the payment was processed I got the journey ticket for one side (Tezpur to Kolkata) only. I immediately contacted their call center & spoke to Suraj at around 3.45 pm today & informed him of this discrepancy. Suraj assured me that the the ticket for the other side i.e Kolkata to Tezpur would be there in my inbox after 45 min. This was a recorded call & can be traced for reference.

I waited till 5 pm; however, did not get my awaited ticket; so I contacted their call center again. This time I was surprised to be told that I’ve booked a ticket for one side only. I lodged a service request with id 1654550 with my grievance for the jouney ticket from Kolkata to Tezpur. However their service team now claimed that I’ve booked a ticket for one side only. This was just not possible, because other websites were selling the same package for price ranging from Rs. 17000/- to Rs,. 18,000/- [Am attaching screenshots of other websites & their prices] So, it is highly unjustified for them to have sold me just one side of the journey at Rs. 15,864/-

I’ve spoke to one of their supervisors called Shailendra; He has claimed to have cancelled the booking & deducted Rs. 1548/- from my booking amount.. He has asked for 24 hrs time to check for discrepancies in the system & has assured refund of Rs. 1548/- in case fault is found on their side.
I would like to highlight how theirr staff has taken a complete U turn on what was displayed on the website at the time of booking, as well on the assurance which was given to me by their staff Suraj immediately after my payment was processed. I’ve requested them to consider these facts as well as the prices of the competitors (screenshots of their prices attached) while deciding on my case. They cannot sell a one sided journey for Rs. 15864/- when a host of other people are selling the return journey for price ranging from 17,000/- to 18,000/- Another website Makemytrip.com was selling the same package at a lower price than goibibo.
They are now harassing by not communicating with me inspite of a number of emails written to them. Their call center executives are not helping either.

I suspect they are luring customers into selecting their site offering the best price & then cheating them by selling them incomplete journey tickets.