custom permalink 404 error only on posts

Hi, I updated my permalink structure from default to /%postid%/%postname%/ and everything navigates fine since that change except I now notice that navigating to my posts gives an 404 – Invalid Syntax! error. I see that the URL displays %postid% for some reason. Ex: https://www.test1.com/%postid%/now-available/

I’m not sure why this only happens for posts but not pages and have reviewed the Permalink codex as I assume this where the solution lies?

Thanks in advance.