Re Mastercard, their own rules state that any other code other than 7995 and the gambling merchant must be acting under the countries applicable laws.
Mastercard do state that gambling transactions will not be refunded however if it is coded incorrectly, by uk law it cannot be deemed as a gambling transaction. However banks are using honesty and integrity of consumers admitting to using gambling websites to refuse raising chargeback.
The FCA say if there is data descrepencies with payments and customer disputes the payment it is not for the bank to decide if a chargeback is viable. (There are cases on FOS website to confirm this I will come back with case numbers) however banks see gambling and deny chargback and it would seem so are FOS in many cases.
If you open a case with the FOS and it is not upheld request all evidence on which they base their decision. I have just won a case as I rejected the decision as when I reviewed the evidence sent from bank it was all related to a previous complaint and held no relevance to what I had raised!
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