A couple of things are likely going on there. One, the green paint is likely a high gloss or a semi-gloss paint. Or, as Coco said, contamination. People do all sorts of crazy things to their walls like cleaning them with Murphy's Oil Soap or Pledge or any number of cleaners that have some sort of wax or silica in them which makes it next to impossible to get anything to stick. Before trying an oil based primer like CoverStain or KILZ oil-based, you could sand the walls down to remove any contaminants and give the wall some "bite" so the new primer will stick.
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