How to update mdf version?

I want to update my mpf version in xampp.

How it is possible?

I need mPDF v7.1.7 version.

composer require mpdf/mpdf This command is not working. Giving error!!

[Composer\Downloader\TransportException] The "https://api.github.com/repos/hillelcoren/omnipay-wepay" file could not be downloaded: failed to open stream: A connection attempt failed because the connected party did not properly respond after a period of time, or establis hed connection failed because connected host has failed to respond.

via Chebli Mohamed