When we copy the Wrapper that is described here: https://learn.microsoft.com/en-us/power-pages/configure/web-api-http-requests-handle-errors#example-wrapper-ajax-function-for-the-csrf-token in the power pages we get error, the documentation lacks information about header.

Editing the header fixed the issue however, so we request to update the documentation with complete steps which will help other users who are referring to the article.