Hello Jaroslav,
Can you make it clearer what you are doing?
Do you test the EAs on a Demo account and when you move to live they start losing?
Did you test your live and demo if they match the trading in the first place? The best way to test your broker is to place 2-3 EA with 0.01 on a Demo and Live and see if the trades will match. If they do not. testing on a Demo account becomes useless.