I invested more than 20,000 US dollars in MIEX. I want to withdraw funds but they let me pay taxes. I also paid. But they just ignored me now

I invested more than 20,000 US dollars in MIEX. I want to withdraw funds but they let me pay taxes. I also paid. I said that I will invest in one to three days. Now it is a week. I now ask the customer service, saying that my account is abnormal, and I have to pay half of the guarantee. You can invest in one day, and now I don’t have any information to contact customer service