u/Extension-Luck4584

So I recently had a verge repair on the roof as I noticed a leak in my sons bedroom. Im very happy with the job the roofer has done and cannot see how it would be letting any water in. But when it rains, the existing water stains and damp patches get bigger. Definitely wet to the touch.
Could there be another cause to letting the water in? For example the rendering, I’m out of ideas as the roof is pretty much solid, any help would be much appreciated.
(The stains appear as if watering is coming in from top down), everything I can see in the attic is bone dry, including roof membrane)