Encounter a scammer

I encounter a scammer on internet. He leads me to invest on this website. I invest fifteen thousands US dollars after registration and he deposit over sixty thousands US dollars for me and make a profit of over seventy thousands for me. When I try to withdraw, the customer service says that I need to pay 10% tax first and it is roughly nine thousands. This is a fraud platform for sure. Please help me to get my fifteen thousands US dollars back. Please contact me if you need any information from me. Thank you so much.