PEI smooth and textured. Isopropyl alcohol works until it doesn't. That is why it is recommended that you use warm water with soap. I suspect the ratio of water to soap isn't dialed in quite right in my case, but I haven't bother to fix it just yet.

Either that, or don't touch the surface with your bare hands.

I think the problems arise from using glue on it.

If I only print PLA without glue, one wipe with IPA and it's clean.

Glue on the other hand, it really sticks and you need water and soap.

I always use IPA to clean the bed too.

I have once used glue for a very thin print with lots of intricate holes in it.