title: How to send a push notification to a particular user at particular time after user's registration?
body: <p>I want to send a push notification to a user <strong>after it's registration</strong> using FCM.
  <br>At the following times
  <br></p>
  
  <ul>
  <li>after <strong>5 mins</strong> of registration</li>
  <li>after <strong>24 hours</strong> of registration</li>
  <li>after <strong>1 week</strong> of registration</li>
  </ul>
  
  <p>Thanks for your help in advance </p>