I have been using Instagram API on my website for a year now and it worked perfectly until today when they enforced the sandbox mode on all applications. Now I get an oAuth error on any request that I make with my client-id. Even simple requests like the following:
https://api.instagram.com/v1/users/search?q=[USERNAME]&client_id=[CLIENTID]
How do I get around this problem? I have checked that I am not calling for more than 20 most recent media in my API calls as suggested by the documentation.
From the Instagram API changelog
All API endpoints require a valid access_token
You need to authorise a user with your app. Even the Instagram account you registered the client with you need to follow their authentication steps here Instagram API authentication.
Note that in Sandbox mode only other sandbox users will be visible. I.E if you try and get recent media for UserA who is not a sandbox users, it will come up as no user found.