Hello,
Thanks for reaching out. Can you please reply privately to us including your request and response logs where 100k user identifiers were included? The operations collection for each AddOfflineUserDataJobOperationsRequest can contain at most 100,000 elements. If you need to submit more than 100,000 operations for a job, send multiple requests with the same job resource_name. This is discussed
here. To make larger AddOfflineUserDataJobOperations requests, please apply for
standard access, which does not have an operations cap. Please see this page for various
API Limits and Quotas.
Regards,
Matt
Google Ads API Team

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