The two cases that we all refer to have two key points. One is a credit card whereby gambling is automatically blocked so an incorrect code is valid and the credit card company should chargeback, this is how I got my money back via Barclays.
And the other one a gambling block was on the card therefore the incorrect code worked for that person via the FOS decision, Chase have done this for me on my other chargeback.
I deal with FOS via work, (unrelated to these issues) and you do need to ensure you cover all points otherwise they will likely side with the bank. Gambling isn’t excluded by VISA/Mastercard or I can’t find it in the terms which I have read numerous times, but you will need to ensure you relay these things to the FOS. If you have used a credit card you should win, if you have a gambling block you should also win. If you haven’t mentioned gambling and the banks refuse on goods not received again I think you will win.
If gambling mentioned and bank refuse then you will need to ensure you check the FOS decisions that have lost and try not to repeat the words in that and use a different tactic, most appear to have failed as they complain the bank should have blocked the transactions that only applies if arguing the code bypassed a block, none of the unsuccessful FOS decision’s mention goods not received therefore that is the route I would go for, even if you have mentioned gambling no goods were received so maybe that would work.
Automatic translation: