I see now, thank you!
It seems the casino is not pleased with the regular bank statement and would like to mark it as their problem. Very user-friendly indeed!
I have a simple question: could the casino provide you with the transaction number? Since it seems to me that the casino is not inclined to take initiative and instead places the responsibility of proving the issue on you, I believe it should not be too difficult for them to locate the specific transaction number.
I would try to "counterattack" by saying to them:
"Could you please provide me with the exact transaction reference number along with an official payment confirmation from your payment provider or bank (for example, a SWIFT/MT103 confirmation for international transfers)? This would allow my bank to quickly check whether the payment was actually sent and help us determine if the issue occurred on your side or during the transfer process."
Not sure it would help, but this all just feels so odd to me.
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