I was in the same department and applied for one post higher vacancy internally.
however, i was not selected for the job despite of my long time experience and conducting more responsibilities than one can handle. since i was not a favourable staff for my manager, i was disqualified and selected the one who was junior than me (by work experience) and little experienced as she was very best friend of the manager. I never used to hang out with the manager after office or during lunch time or gathering so he didn't like my way of living and prioritizing my personal life after office.