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Step 5. Follow steps here to place the Tracking ID on your site
Step 6. Consider handling duplicate conversions in Google Analytics. Setup a tag with transaction_id.
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Create a data layer variable and point it to “ecommerce.purchase.actionField.id” to avoid duplication.
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Step 7. Consider handling duplicate conversions in Google Ads
https://support.google.com/google-ads/answer/6386790
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