Movie

Hello.

I cant remember the name of one movie.I think it was french.3 school girls make session with cards for some ghost.And they wake up this ghost.but only one of the girls and her small sister have problems in the flat where they live.the girl die in the movie.And end of the movie show police investigation and old short videos that its true story.If you can help me with this i will be very greatfull.

Thank you