Since 01 Mar 2018 I opened a support ticket #772767 on @Poloniex and still without answer. I have a withdrawal Status: "Complete: Error". Get out of this exchange as soon as possible.
You need to send support tickets and wait for feedback because they have a lot of problems to solve now. Circle bought Poloniex, so this time is undergoing audit and transfer. I think Poloniex is still reputable.