Development mode error

good day, I have problems when entering the BLYNK app through facebook, because every time I try to enter I get an error that says the following: application not configured, this application is still in development and you do not have permissions necessary to access it, it should be noted that previously it entered normally and for 2 weeks I no longer have access due to this error, what can be done to solve this problem?

Have a great day Thank you very much!

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