If you lose your user account password, simply go to the "My Account" page on the website or on the home screen of the "My In&box" mobile app and click on "Forgot Password".
You will then receive a new password by email, which you can later change in your user account. Note that depending on your email service, it may take a few minutes for the email to arrive.
Once you receive the new password, you can log in to your user account with it and change it afterward:
Reset my password on the My In&box mobile app
In the My account tab > My user information > Modify your password:
Reset my password from the website
In the My Information tab > New Password: