My unity ios build is taking more than 2 hours

Hi to all, Generally my build use to take 2-4 mins to build an ios/android game pervious but after i ticked the static box for a large fbx file, from then after it is taking more than 2 hours. what might be the problem and is it right to tick the static box. I ticked the static box because it will take less to draw calls which increases performances to all platforms . So can you explain me what causing the problem and what im thinking is correct about static box(draw calls).