Hi @srividya.c !
Thank you for reporting! Looking at this topic and this status page, there was an issue with the Android Guardian app that has been fixed with the newest version of the app, thus the recommendation was to update the app.
Some additional checks can include the end users phone settings like enabling push notifications and disabling “do not disturb” mode. Also, checking if the date and time on the phone is set correctly (or set to be automatically updated).
If the above won’t help, please let us know!