You can get this error when your application is inaccessible to the public (the large slider on the Status and View page of the Facebook developerβs control panel says βNOβ), and you did not add the account you are logging into as the test user in the application .
I had such a situation when I had not added my test user (I use a difference than my personal one for testing) as a test user for the application.
You can add your test users to the Roles page of the Facebook Developer Control Panel.
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