I cant insert the productivity modules when using the heavy oil recipes provided by your mod, but they are available in vanilla. See images attached.

https://imgur.com/a/3Kg23vj

Having a quick look, I can see that the productivity modules in vanilla do show up.
https://imgur.com/a/Yd8YQjX

I notice in your picture you have more modules than the standard module 1-3s. My guess is that mod is causing the issue, since every productivity module needs the allowed recipes added to it.

Could you tell me what mod you have that is adding adding the extra modules?

I am using space exploration that is making new modules. But the other recipes added by your mod have all the vanilla modules + space exploration modules available.

The Cation Ion and and Anion Ion exchange bead recipes from Space Exploration cannot take productivity modules of any kind. The recipe from pure Space Exploration can take them normally.
https://imgur.com/a/PCP6IGA

Hello, sorry for somewhat necro'ing this thread, but I can replicate this bug with exactly two mods installed: Space Exploration and GDIW.

Productivity modules cannot be added with the GDIW Crude Oil Processing variants, but they can be added to the Space Exploration original.
This bug does not hold for the Advanced Oil Processing recipe from Space Exploration, whose GDIW variants can be Prod Module'd.

I did not check dustgold's bug, but I imagine it's similar.