invalid SL issue

please I am facing this problems since last week, when ever I put my SL they use to say that its invalid SL and most of the time I used to faced such kind of problems. unfortunately when ever I putted 10 pips SL they used to show me that its invalid until I put more than 50pips SL or even more than that before they will allowed me to enter the market which is wrong. what hurt me more is that I loss a lot of setup and a lot of opportunity in the market last week