Withdrawal deducts 20 dollars for handling fee

I do not want to trade at this small platform anymore. The withdrawal of 93 dollars deducts 20 dollar handling fees. It can only contact via email. I ask the customer serivce and it said that they have hint that withdrawal for less than 100 dollars has a 20 dollars handling fee. I check on the website and there is only small line for the hint. I can only blame myself for careless. I admit it. I ask other platform and they only charge 3 dollars at most. I remind everyone to stay away from this kind of small platform.