you said other exchanges allow you to withdraw it in 45 minutes.
but right now you are saying they are the only one who sell it (opening the market for this project),which one is true ?
lets talk about the issue,
did you check the network status on cryptopia ? or the project itself.
you should know,lately many project created 2 differents chain because of network issue.that means it has a possibility that your withdrawal went to another chain.
ask it to them(developer team and cryptopia team) about it.