P.S. I am running on 1.16.3

Happened with Roma mod to me. Unfortunately this tends to be a rather nasty trial and error scenario.

Try verifying the integrity of the files first. If not then I did the following

What I did for the other mod to work.
1-Deleted everything in the mod folder
2-Without launching the game unsubscribed.
3-Verify integrity of the files
4-Subscribed to the mod
5-Launched the game but left it at the launcher and the mod menu. Is tayed here for about 15 minutes
6-I closed the launcher and relaunched steam. Then it seemed to work.

Tried it. didn't work :/ it's not appearing in the mod file
What patch am I supposedto be in?

Ok. Go to settings and betas. Unsubscribed from betas. The newest Path for EU IV, is 1.17, although if you google it you'll find the patch note history and the checksum.

The mod works no for 1.17

What has ocurred to you has only happened to me one time, and it was in 1.12.

The only answer I had to whatever was wrong with my pc was:

Ensure I first tried to get the latest patch for the game. Unsubscribed from betas in your settings.

If not, start from scratch and I do mean from scratch.

Delete local content, backup your save files to another location than in documents. Delete the paradox interactive folder from my documents. Ensure steam folder has no folder of Europa Universalis IV. Unsubscribed from the mod. Then download the game from scratch. Depending on your internet connection this may or may not be a big issue.

That was my solution at that point. If that doesn't work, then I got no clue how to help you, I'm sorry.

P.S. Im using a mac. Thought I should let you know (I dont know if that affects anything)

Same thing happens to me too. i will try to some stuff john shepard suggested.