Unable to withdraw

At first, they said my credit score was not enough and asked me to pay 12,000, then they told me that I needed to pay 20% of tax , then they told me that I had 2 suspicious money flows and asked me to pay 6,000, then they told me that it would take a week to review the money, then I kept asking them, and they thought I was too annoying. The deadline is 1/24 and they say they will withdraw the coins, but I think I've been cheated, what should I do? The exchange I checked on the Internet can not be found