Prerequisite:
You need to enable 2FA on your MauPass profile by going to a post office. You should bring your National Identity Card.
You should enable Mobile Authenticator on your MauPass profile to be able to use OTPs generated through the MauPass Authenticator.
Refer to https://www.youtube.com/watch?v=R8qC7GvTb20&feature=emb_title

You will need to enter your username and password to login to the mobile application.
If the app is being used for the first time, then a security code will be sent to you by SMS or Email (which ever has been activated on your profile) and you will need to enter the code on the mobile application for activation.