Why is my paint peeling????

[Cobblersandhogwash]

So I have cut in the edges of the walls.

Then I started rollering emulsion on the rest of the wall.

It dried a bit - 5 mins - and then started peeling off.

Why? Is the wall damp?

Why did it only peel when I rollered and not cutting in with a brush?

So frustrating.

Is it going onto a freshly plastered wall if so Has the wall been most coated?
What kind of paint are you using?