Hello,
Previously, we were able to successfully add Instagram embed links to the embed field within articles. However, this functionality seems to have stopped working. When attempting to provide an Instagram embed link in the field, the following error is returned:
Hello @hoaithanh.phamtruong,
Welcome to the community 
Prismic doesn't support links that oEmbed doesn't support - if you're getting an oEmbed error, it's usually related to oEmbed. The error message you're getting should help you get to the bottom of this: to use 'oEmbed Read', your use of this endpoint must be reviewed and approved by Facebook. Per oEmbed/meta documentation, this is something you need to apply for: oEmbed Read - Graph API - Documentation - Meta for Developers.
Is this a process you've already gone through?