Remedy to eliminate orange-peel/rough patch after final-Coat

[coolusee]

I had applied 3 coats to a wall to get rid of rough surfaces or orange peel effect but inspite of all my efforts there are still small sections where I can see the rough surfaces or orange peel effect.
Is there anyway I can rectify this like sanding and repainting only those sections down without making things WORSE or its too difficult a task to do for a first timer.

 

[joe-90]

Take all your new paint off and sand back with 60 grit then 120 grit. Then undercoat and sand lightly with 120 grit. Then top coat. You MUST use that expensive green sandpaper, anything else is a waster of time.

If the area is too extensive then don't do anything for a few weeks until your paint has fully hardened then sand back as above

 

[coolusee]

I am confused why the orange peel effect comes up ?
Is it because i am thinning the paint too much (over-rolling) or its too thick enough ?
I am using the standard harris 9 inch roller and apply it on the wall in a section of 2.3m * 0.25 m of area rolling it in a long W pattern from (top-bottom)

 

[joe-90]

I don't think you mean orange peel, what you are describing is roller stipple. Use a short hair roller and thin the paint a tad.