Comparison doesn't work

Hello,
I want to use cURL with PHP to compare two PDF files.
I’m passing two PDF files with credentials (Bearer in header request) but it shows me error 400 for format not supported : File of this format doesn’t support comparison. Perhaps you have specified an invalid file extension or the file is damaged.
When it’s not this message, i have this return : CloudFront attempted to establish a connection with the origin, but either the attempt failed or the origin closed the connection.
We can’t connect to the server for this app or website at this time. There might be too much traffic or a configuration error. Try again later, or contact the app or website owner.

Can you help me please ?

This topic has been moved to the related forum: How To Compare Two PDF Documents in PHP With GroupDocs.Comparison REST API? - Free Support Forum - groupdocs.cloud