Triangle corners/length limited marks doesn't show on clip


Hi all, i set the lengh to 15sec for this Mogrt file, but when i drag the file to premiere pro, it doents show the white triangle/corners, (i don't want people to strench the lengh of the clip any longer, that's why i set the time limits, also i checked all all sub compositions are all 15sec... ). do you know why that corners doen't show?
please help. thank you.
