How to connect Crash Bash

Hello, I downloaded Crash Bash for nostalgia and ended up getting a few other games after.

I set up a retro achievements account for Crash 1 and have now started Crash 2.

Crash Bash shows up on retroachievents however within Duckstation it says N/A for achievements.

Can somebody let me know how to connect this game to the website? I’ve already beaten it fully so I think I’ll have to run it back but just curious.