Hi Wei,
Thank you for reaching out to support. Based on the details shared, if the account only contains Universal App Campaigns, these details will not be returned in using Geo Performance Report as it is not supported for this campaign type. You will need to use the supported report types available
here. If you're generating the reports for any other campaigns and seeing this discrepancy, could you please share the report query along with the client customer Id using
Reply privately to author option.
Regards,
Bharani, Google Ads API Team

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