Suffer huge losses after closing the position

The broker in Horseforex leads us by EA. When the customer deposited, he only cared about his own handling fees and ignored the customer's interests. So six customers were unwilling to invest anymore. They decided to withdraw when there is a 15 percent floating loss with their account. So I changed my password on MT4 and closed the position. The account couldn’t be logged in within an hour after closing the position. And there are huge losses about 50%. Then we communicated with the broker, he handled three accounts, but the other three accounts aren’t be handled.