The problem is solved, I thought I would share with you what happened:
Online casinos always have a number in their URL (for example, Fatpirate1.com).
During the 3 weeks when I reported a problem with the payment, the site redirected me to Fatpirate4.com. After 3 weeks, the site switched back to Fatpirate1.com. At first, it only allowed a maximum of 5,000 HUF to be withdrawn, but after a few days, it allowed an amount equal to the daily maximum limit.
I don't know why online casinos change their URLs, but that's what caused the problem for me.
So the solution to this problem was to wait 3 weeks...
Thank you again for your help everyone!
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