Verifying SKAdNetwork Install Validation Postback

Hi, I am updating our system to validate installation postbacks. I am working off of this documentation:

https://developer.apple.com/documentation/storekit/skadnetwork/verifying_an_install_validation_postback

However, I am unable to validate the sample postback that is provided in the documentation. Has anyone else run into this issue? I the provided postback valid, or is it just an example of what one might look like?
Verifying SKAdNetwork Install Validation Postback
 
 
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