I can't unlock the fast breeder reactor.

I can't unlock the fast breeder reactor.

First, I used up about 3000 MOX fuel units.

Next, I researched and completed development of the fast breeder reactor.

However, the spent MOX fuel requirement wasn't met.

After that, I used up about 200 more MOX fuel units, but the requirement still wasn't counted.

Please help.

You should attach a save file.

The save file was too large to upload.
Is it possible to download it from the shared link?
https://drive.google.com/file/d/1rSH-b_kbYzkF3nPmYLScg0gYm4_VOgol/view?usp=drive_link

It was locked in the research tree, but I was able to build it.