Discovery Vitality travel - lack of responsibility.

I am shocked at the lack of response and responsibility taken by Vitality Travel. I booked a trip from CT to Split, the route took me via London for 1.5 hours. Nowhere was I alerted to the fact that I would need an in-transit visa. I got a Schengen visa, called BA and asked if I needed an in-transit visa and was told I did not. I left CT for JHB to get my connecting flight to Heathrow. As I was boarding the flight the attendant stopped me and said I could not fly to the UK without an in-transit visa. One other and I were removed with the assurance that we would get a refund. (The previous day 17 people had been removed from the flight with no Visas). Given that my partner was already in Europe, and I had booked and paid for accommodation, I got another flight via Amsterdam at a much higher cost. It was a Friday after 5 and I tried to get hold of someone at Vitality which was impossible. I used the Vitality Bot which didn't give me options that were appropriate. Once in Europe I again tried the Bot which gave me an email address. I wrote to them and also requested to cancel my return flight since I would not be able to use it. I have had no response to any of my emails to date. Once back in SA I called Vitality, (3 times as the 1st 2 agents did not get back to me.) Each agent had only tried to get a refund from BA who showed my status as a no-show, despite my email to Vitality cancelling my return flight. The 3rd agent advised that BA would not refund me and that there was nothing she could do. I believe that Discovery is responsible for this as there was no indication that I needed an in-transit visa. Despite further emails to Vitality, I still have had no response from Vitality.