Hi Everyone!

Last year I successfully recovered nearly £4k from Emirates (credit card chargeback) for a cancelled flight that they refused to refund, and this week I have received an email out of the blue demanding the return of the money in cash in order to ever fly with them again. Obviously I won't be paying them for a flight that they cancelled so I guess I'll take that as I'm banned for life. Below is the story in a nutshell (apologies it's a bit long winded):

I was going on a guided tour of Japan, I've always wanted to try Emirates first class so I thought I would treat myself as I had recently gone through a tough time (split up with my long term girlfriend).
Then the floods happened in Dubai, I was chauffeured to my departure airport (BHX) in good time and everything seemed well.
While in the queue with the business class passengers for the first leg (BHX don't do first), there is a commotion and screens at the check in desk change: FLIGHT CANCELLED CONTACT EMIRATES CALL CENTRE
After approx an hour the airport staff arranged for another taxi back home, but nobody contacted me and Emirates were completely un-contactable. Their number was permanently engaged and their web chat was down.
S**t happens, I thought, so I booked alternative travel with Air France (one way) and assumed Emirates would refund me for the outbound journey and hopefully give me a ton of free miles or something for the inconvenience.
8 days later, I was able to contact them via web chat to enquire about whether the return ticket was still valid and the agent said they would re-issue my ticket and I would be good to go, I also asked about what refund I would be due for the outbound journey but they said I would have to fill out a refund request form after I get back. Whatever, I thought. Slightly annoyed that it would not be automatic.
The return Journey was perfect and everything I expected first class to be, but now it's time to get my money back for the cancelled flight, because I have a credit card bill to pay for the Air France flight.
I fill out the Refund Form, using the original ticket details, a few days pass and I get an email, My Refund request has been rejected as the ticket was re-issued and I should use the latest ticket number
Annoyed, I fill out the second refund form, exactly as before except with the new reference
Weeks go by, radio silence, I chat with their agent again (third time), they said it could take up to 21 days, frustrated by now I write: Refunds should happen automatically when the flight is cancelled by emirates and customers should not be made to jump through hoops. I'm a regular premium flyer, please make this right otherwise I won't be using emirates again. I'll give it the 21 days and then you will hear nothing further from me, I will initiate a chargeback through my bank
So that's what I did, amazingly they tried to challenge the chargeback claiming the ticket was re-issued and 'fully utilized', it wasn't, but ultimately my bank were able to challenge this and succeeded. Apparantly they eventually agreed to the charge back before it went to mediation through Mastercard, which apparently carries a heavy fee. I also raised a complaint with the CAA because by now I was absolutely furious with them.

Fast forward nearly a year later to this week, I receive this:

In connection with your ticket XXX XXXXXXXXXX, under booking reference XXXXXX, we have received a dispute through your bank and the same was also received through our acquirer World Pay.
Having reviewed the ticket history, I noted that it was reissued and utilised.
Details of the dispute, Order code - XXXXXXXXXXXXXXXXX Ticket number: XXXXXXXXXXXXXX CASE NUMBER - XXXXXXXXXXXX
You are required to settle the payment for your ticket in order to enable your travel with us in the future. In such cases, recovery is made only in cash.
Please contact our contact centre or the nearest office in order to resolve the issue due to high order value and utilisation of service.

I sent them a strongly worded response telling them to literally go swivel about a week ago and I have heard nothing back but now I'm thinking am I going to be put on some sort of no fly list in the UAE or get arrested there should I ever have to pass through the country.

What do you guys think I should do next (if anything)? This is highly unfair considering I have done absolutely nothing wrong. Do you think the press would be interested in something like this? It seems to be like some sort of systems glitch combined with the ticket re-issue where I have only taken the return leg. They can't seriously expect customers to forfeit the price of the outbound tickets if they decide to take the return? In hindsight I should have booked a return journey with Air France and it would have been much more straightforward.