Goibibo India Private Limited - Excess baggage not given

I booked tickets from Bangalore to Paris on the Goibibo website. At the payment stage, there was an option to select excess baggage. I paid INR ***** for it. There was no indication that it would only be applied to the domestic sector of the flight. Finally, when I got the ticket, I realised extra baggage of **kg was applied only from Bangalore to Chennai and not my further flights. I called up Goibibo on May **. They said they would get back to me within ** hours - they didn't. I called up again and again for a whole week and followed up and social media and did not get a response until the **th where the Customer Delight team said it was not Goibibo's fault and I would not get a refund. I went on their website to click screenshots of their faulty page and found out that they had fixed the issue by putting a notice that extra baggage is only applicable to the domestic flight! They are refusing to call me back and resolve the issue. It has been ** days. I have been unable to apply for my student visa because I do not know if this is the flight I will be taking to France at this juncture.