Hi Isabelle and Mayank,
The University of Edinburgh Moodle site is not currently configured to allow access to the Moodle mobile app. See this FAQ for more details:
We are working to configure Moodle so that it will allow students to log into the app with their normal University credentials. Once this work is complete we will make Moodle accessible via the app.
We will announce this via the News forum on this course when it is ready to use.
Wesley