Greetings to you too!
As far as I can guess, this is called a "verification deposit." The purpose is to verify your preferred payment option in order to be able to receive the winnings, usually after the deposit is wagered at least once.
A newly registered player has never made the deposit; thus, the payment option needs to be verified in order to receive the winnings by the very same now-verified method.
But this is just my opinion. Could you kindly let me know whether I made a good guess, please?
There is another alternative I'd like to exclude from consideration. 🙏
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