Open your browser and head to the login page https://tass.riverside.qld.edu.au/ParentLounge
Use your Parent code (also called Account number) as your username. Click/tap on Forgot Password
Enter your parent code as the username, your email address used for receiving Riverside emails and the Security Code shown (changes every time) and click/tap Save
Check your email, including SPAM folders, for an email from email@example.com similar to this and click/tap on the link included in the email.
Choose a new password and enter it in both boxes then click/tap Save.
You should get a confirmation pop up.
You can now return to the login page and log in using your new password.