Hello,
If you are making a request targeting a child account, but authenticating from a managing account, you must specify the managing account customer ID as the
login-customer-ID, and specify the target child customer ID in the payload. You can then retrieve campaign information from the child account. For example, you can query the
campaign resource for campaign.start_date and campaign.end_date. However, these attributes only give the date, not the time.
Regards,
Matt
Google Ads API Team

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