Same^^^^^
I got zero passenger in one line, even after i deleted the parallel bus line

And I also have few (like 3-4) passengers in my airport line. The volume went up to 2000/week after I switched to ground stations

Btw I also tried to used the longest platform, depths, angle, type of platform. It just randomly not working for some of the stations

Yes, I got the same problem. It seems that the issue are the internal paths of underground stations. When I didn't modify them, people started to return. However, after a while people stop coming to the stations. I got tired and removed the mod tbh.

@creat89
@Billy S

I had the same problem for a year. Nobody uses my metro\underground (built with MOM) station even when it was the only one transport in city. Citizen perfer wait overvrouded buses on overcrouded stops. Mod - Stops and station helps me.

https://psteamcommunity.yuanyoumao.com/sharedfiles/filedetails/?id=1776052533