I've had this happen before and for me it was caused by another mod conflicting with it. I had the same issue when I had the realistic naval manpower mod, and it fixed as soon as I turned that off.

As TS said, this is likely a mod conflict. What other mods, naval focused ones in particular, are you running?

So im running.

-RGFX- Clean Menu Fonts / Improved Battle Plans / White Map Font
-Operation Overhaul-
Better Gameplay - Resource Stockpile
Border Conflicts Everywhere
Colored Airforce
Colored Buttons
Coring States 2.0
Decisions & Formable Plus
Formable Nations
No XP limit
Puppet Manager
Subs Not Useless
Support ARmor
Toolpack


Now lets say i remove Operation Overhaul, than i get the normal Japan navy tech.
And when i add Roade 56 i get their navy tech.

So im kinda confused as to what mod is adding the false navy tech, as most mods that i do have on are just quality of life mods.

Subs Not Useless is my guess given that it's naval focused. Also you NEED to have Expert AI for this mod to work. Please enable it.

EHhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh, Expert AI crashes my Game ^^"

It works just fine without it, but yhea besides that one Techtree thing.

But no Subs Not Useless is not it, i tested it.
If i remove Operation Overhaul / Roade 56 , and have Subs not Useless on i get the normal vanialla techtree.

Sorry, this mod will not function without Expert AI, I cannot help you if you do not have it enabled.

Uhm, yhea.

I tried to run Expert AI & Operation Overhaul and it crashed instantly.
So there is that :/

Thats why i been playing without it

Like I said, our mod cannot function without Expert AI. Unless you disable the mod conflicting with Expert AI, and run Expert AI, I cannot help you

Btw, it all works now, even with Expert AI?
Even thou i did nothing...


.... Technology~

You likely disabled a mod that was conflicting, or that mod fixed itself.