If you have forgotten your password, you can reset it by following the steps below.
1. Click "forgot password" on the login screen.
2. Enter the email address you are using and send an email to reset your password.
3. Click on the "Change password" button in the email you received and set a new password.
(Body in the email)
4. Set a new password and you will be able to log in.
Note: In Japanese「パスワードを忘れてログインできない」https://workcloud.zendesk.com/hc/ja/articles/220178167