i'm developing a website that enables user to see and manage his Instagram posts and comments.i want to get advanced permissions by app review of Facebook. i have created a Facebook app with some test users. then i created test page's for them. but the problem is i can't connect Facebook test page to Instagram business account . it gives me this error:
sorry , an unknown error occurred , please try again.
what should i do to connect Facebook test page to Instagram business account?