Flow-Flow must be authorized to pull photos from Instagram onto your WordPress website.
Here is one way to do that:
1. Login to Instagram.
If you need to connect your client’s website to their Instagram account, then you will need to get credentials from your client.
Depending on the security of the account, you may need a security code. If so, do not use the back button once you are logged in, as it may give you this type of error: Array ( [error_type] => OAuthException [code] => 400 [error_message] => Matching code was not found or was already used. )
2. Login to your website and go to the Flow-Flow settings.
3. Click the AUTH tab at the top.
4. Scroll down to Instagram auth settings and click Authorize.
5. Click Authorize again in the screen that follows.
Double check settings:
You should be able to see the Access Token and Log Out button in Flow-Flow.
And you should be able to see application authorized in your Instagram account at https://www.instagram.com/accounts/manage_access/
If Authorize fails:
If the authorization fails, try to revoke access in Instagram (screen above) and also Log Out in your website -> Flow-Flow -> AUTH -> Instagram auth settings (2 screens above).