Newbie broker problems?

now a graduate in school of pipsology. working demo accounts with fxcm. all of a sudden im finally clocking pips on nzd/jpy…s/l set at 70 above buy in. reaches 300 pips above buy and they wont let me close out order. was that just a gank (ganster) move or is that usual? Anyone know any reputable brokers…please would appreciate it.