Hello Diogo,
I see that you are still using v1, I recommend you to upgrade to the
latest version of the API and try again. In general the PERMISSION_DENIED error occurs when the user making the API call(authenticating the OAuth) might not have access to the account or to the manager account. Please share email address of the authenticating user, the client customer id and login-customer-id to investigate further. Please use
reply privately to the author option while sharing the information requested.
Regards,
Sai Teja, Google Ads API Team


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