I am guessing they are restricting your withdrawal because they are performing an investigation. I just did a quick read on their ToS, and it was mentioned there that gamblers might be subjected to a thorough investigation in case of a large win($24k is a big amount of money) and the investigation can last for hours or days. In the meantime, I'd say remain in contact with their support and get as much information as possible about the issue, but if you already did that, I'd suggest posting the conversation you had with their support here to let the members see what has been discussed and the progression of your case.