Instagram Introduced a new API called content publishing API, this API will Instagram Business account users to publish or schedule posts in their feed from the third-party apps or website. Currently, this API will support scheduling and posting of a single image or video posting, and scheduling of the carousel is not supported. This API will let each business account user publish or schedule 25 posts in 24 hours from a third-party platform. Additional post can be published from Instagram's mobile app or creator studio
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