Hi Charlene,
In the AdWords API, the service that is similar to the Change History would be the
CustomerSyncService. However, the changes that were made in your account that can be retrieved here are limited only to the objects and fields that you can find in its documentation (ex.
AdGroupChangeData,
CampaignChangeData). As for the list of users who made the changes, I'm afraid that this is currently not supported in the said service.
I hope this helps.
Thanks and regards,
Peter
Google Ads API Team

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