Here: https://developers.facebook.com/docs/graph-api/advanced/rate-limiting

Page-Level Rate Limiting

These limits apply to calls made using a page access token. Your app will receive error code 32 if you hit these limits.

The blog post at https://developers.facebook.com/blog/post/2016/06/16/page-level-rate-limits/ provides a detailed explanation of page level rate limiting.

and here: https://developers.facebook.com/blog/post/2016/06/16/page-level-rate-limits/