Hi,
To update the custom conversion goal, you'll want to send a request like the following example, with your customer, campaign, and custom goal IDs substituted.
{
operations': [
{
'update': {
'resourceName': 'customers/YOUR_CUSTOMER_ID/conversionGoalCampaignConfigs/YOUR_CAMPAIGN_ID',
'custom_conversion_goal': 'customers/YOUR_CUSTOMER_ID/customConversionGoals/YOUR_CUSTOM_CONVERSION_GOAL_ID'
},
'updateMask': 'custom_conversion_goal'
}
],
}
Note that you'll want to include the
updateMask as shown above to indicate to the API that your intention is to update the
custom_conversion_goal field.
If you previously encountered an
IMMUTABLE_FIELD error with the message "Field 'custom_conversion_goal' cannot be modified by 'UPDATE' operation", please try your request again. That error was due to an issue with the API that has since been fixed.
Cheers,
Josh, Google Ads API Team

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