um i have so many files - this is the

[small halo]

er yeah, so you're probably trying to access window.something while vercel/nextjs is trying to pre-render your page on the server (and the server isn't a browser so it can't run it).

Depending on what this code is you'll need to put it in a client component for e.g. If you don't know what this code is then probably better to read through https://nextjs.org/docs/app/building-your-application/rendering/client-components

It's pretty simple to resolve this once you know what code is causing it