Hello,

I'm guessing you have not installed the package tuleap-plugin-pullrequest or not enabled the plugin in the site administration. If need more information on how the plugin works, you should take a look at the documentation: https://tuleap-documentation.readthedocs.io/en/latest/user-guide/pullrequest.html

That's said, this tracker is not a support tracker. The Tuleap community might however be able to help you. If you are in need of a professional support, please note that Enalean propose such service: https://www.tuleap.org/get-help#professional-support