Why is my freshly applied paint coming off on the roller?
When your roller lifts the existing coat of paint from the wall surface it indicates that the wall was not prepared correctly or possibly something is affecting the bond to the wall (like moisture or heat).
Although the newly primed paint isn't pealing off the wall it would be wise to check that it has a good bond. Use a putty knife to try and scrape the paint from the wall. It should not come away if it has a good bond to the wall.
If it does scrape away continue scraping until it doesn't. Verify the primer has dried securely to the wall.
Sanding the walls wont help if the problem is with the original paint not being applied to a clean surface. The problem is contaminants preventing a proper hold from the paint.
Dulux is a very good paint brand. Check the label for any &quot;warnings&quot; the manufacturer may have.