Why do hashtag searches on Instagram only return posts from the past 24 hours for new searches?

By design, the Instagram API only allows us to retrieve posts from the past 24 hours. (see Facebook API page) Because of this, when you first add a new hashtag to watch, we can only retrieve results for the past 24 hours. Other networks, e.g. YouTube, Twitter, do not have this limitation. 

Also, Synapview will also only retrieve a maximum of 50 new posts per hour for any one hashtag you have saved. If you are watching a hashtag that has more than 50 posts per hour, please contact us