Hi Julián,
The
USER_PERMISSION_DENIED error occurs when the account is not linked to an MCC that can directly manage accounts. Another possible reason is that the OAuth2 credentials used has no access to the specific client account. Could you please make sure that you're generating the OAuth credentials by logging in as a user who has access to the Google Ads account? If you're generating the credentials from a manager account, and are accessing a related customer account, you will need to set the
login-customer-id header to the customer ID of that manager account, removing any hyphens in the ID. If you're still seeing an issue, could you please share the email address used for authentication along with the error logs using
Reply privately to author option, so I can take a look?
Thanks,
Bharani, Google Ads API Team

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