Problem display bearing and track

Hello
From any meridian measured bearing point?
if you combine track and bearing in flight is not the point!?
Why different bearing (BRG) on the displayed page from the bearing by pressing the point?
Flying along the meridians
From any meridian measured bearing point?
if you combine track and bearing in flight is not the point!?
Why different bearing (BRG) on the displayed page from the bearing by pressing the point?
Flying along the meridians