Sometimes, emails can be labelled as junk based on what email provider they're using. If they still can't receive it after checking, please follow the steps below:

1- Click on 'send password update email' from 'login actions' (parent 1 details)

2- If they still don't receive it. Copy/paste from comms log (you will then have access to that email) to your personal email (school management system) and send it from there.