u/Just-Muscle7572

Hi everyone, I’ve been painting our rather large house and so far so good (antique white). But I’ve just done our media room and I’ve got this patch on the ceiling that looks like some kind of oily bleed?

The roof was a dark blue. I cleaned it, painted it with a grey tinted primer and then two coats of the top colour. I didn’t sand it prior to undercoating it.

Any idea what I can do to fix it? My gut says that vissner BIN and a full ceiling repaint but I’d like to avoid that.

Edit: forgot to attach the photo