Conversions missing from Facebook Ads Manager is a common issue that many Facebook advertisers are facing. In this article we try to highlight two most common yet obscure reasons why transactions may be missing from Facebook and offer ways to solve Facebook tracking and attribution.
Reason 1: Deduplication
Facebook often recommends advertisers to send conversion events to Conversions API in addition to sending same events to the Pixel and provide a deduplication parameter to prevent same event tracked twice. While well-intended, this advice is designed for a narrow use case when JavaScript is blocked in the browser, allowing Facebook to attempt to attribute conversion using customer details available on the back-end alone. In practice it often reduces amount of data available to Facebook to match the conversion to the ad interaction.
The primary reason for this is that Facebook Conversions API deduplication parameter makes Facebook to ignore the event sent to Conversions API altogether when a corresponding Pixel event is available, even if Conversions API event has more customer data.
Sending same conversion to Facebook Pixel and then sending customer details to Conversions API with deduplication parameters will result in the Conversions API event being dropped by Facebook Conversions API in most cases.
This is often the case in Conversions API integrations offered by companies that don't specialize in attribution.
Able Customer Data Platform solves this limitation by merging in-browser customer identifiers, such as Facebook Browser and Click Ids (fbp/fbclid), with the customer details that are available on the back-end and can be used by Facebook to attribute the conversion such as customer email, name and address. It then sends it to Facebook Conversions API as a single event, combining the details that would normally be sent to Pixel and API separately allowing Facebook to use both for attribution.
Reason 2: Modelled Conversion Settings
When Apple introduced tracking and privacy restrictions, it's primary goal was to stop ad platforms from collecting data about external activities of users. Facebook complied with the restrictions by removing click id parameter from IOS clicks and relying on browser identifiers and non-personally identifying parameters instead. Facebook implemented a method it calls 'modelled transactions', which uses partial details such as depersonalized identifiers and personal details sent via Conversions API to guess, which ad click produced the conversion.
While the method works fairly reliably, Facebook severely restricts what events and what attribution windows can be used to comply with privacy restrictions. Advertisers need to ensure that the attribution settings that are used are compatible with conversion modelling; otherwise Facebook won't be able to attribute IOS transactions correctly.
The latest official announcement at the time of writing this post states: "We are introducing modeled reporting for our 1-day click-through attribution window that accounts for events no longer reported. To adjust for data sharing limitations, we will not use modeling for our 7-day click through and 1-day view through attribution windows. Reporting for these attribution windows will be partial and not include all events."
Using unsupported attribution setting in Facebook will mean that even the conversions that can be attributed from the Conversions API data sent to Facebook won't be shown because of privacy limitations.
Detailed information about recommended conversion window settings is available on Facebook website: