Hi Darren,
Thank you for reaching out. In order for me to take a closer look into why you are receiving this error, can you please provide the complete detailed logs of the request and the response along with your customerClientId? You can enable logging by following
this guide. When providing this information, please
"Reply privately to author." If this option is not available to you, you can email us directly with this information at
googleadsa...@google.com.
Yes, you can use this service to upload multiple conversions at once.
Regards,
Danica, Google Ads API Team

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