I have a list of checkboxes, like

Notifications:
First Email
Second Email
Third Email

i want to update(check/tick) the 1st option "First Email" when "if" condition gets true. What i have done so far

(On Edit -> On Success)

if(input.Email == " xyz@email.com"){

      Notifications.select('First Eamil');

}

This doesn't work. I am getting the alert like this " 'Notification' can be used only in on load actions". This works in "On Edit -> OnLoad". But i want to do it in "On Edit -> On Success".

Kindly guide me, how it can be solved?