No Document Import in Page
Prevent importing
next/documentoutside ofpages/_document.js.
Why This Error Occurred​
next/document was imported in a page outside of pages/_document.js (or pages/_document.tsx if you are using TypeScript). This can cause unexpected issues in your application.
Possible Ways to Fix It​
Only import and use next/document within pages/_document.js (or pages/_document.tsx) to override the default Document component:
import Document, { Html, Head, Main, NextScript } from 'next/document'
class MyDocument extends Document {
//...
}
export default MyDocument