If you have an existing server-to-server integration with a third-party measurement provider, you must use the adapter URL Amazon Ads provides, you cannot use a pixel.

When you have an existing server-to-server (S2S) integration with a third-party measurement provider, Amazon DSP requires the use of a specific adapter URL. This URL acts as a bridge, ensuring that the data from your S2S integration is correctly attributed and processed within the Amazon Ads ecosystem. Using a pixel in this scenario would bypass the S2S integration, leading to data discrepancies and inaccurate measurement. The adapter URL is designed to work seamlessly with your existing S2S setup, providing a robust and reliable method for tracking conversions and other key metrics. Therefore, you must use the provided adapter URL and cannot substitute it with a pixel.