title: How can I receive multiple notifications by using GCM without replacing the precedent one?
body: <p>I'm working on a project which receive notification from GCM server.</p>
  
  <p>I've got the registration ID from GCM server and i send it to my server application which save it in the database.</p>
  
  <p>My device receive the message but when I try to send another one, the precedent is replaced.</p>
  
  <p>I know that we've 2 types of message:</p>
  
  <ul>
  <li>Collapsible "send to sync"</li>
  <li>Non-Collapsible</li>
  </ul>
  
  <p>So without changing the name of the message, how can I get two message send at different time?</p>
  
  <blockquote>
    <p><strong>UPDATE 1:</strong></p>
    
    <p>When my device is offline (for example airport mode activated), I try
    to send for example 2 messages from my application server to Google
    server (I read that Google stores all the messages). But when I
    desactivate this mode, I receive only the last message sent.</p>
    
    <p>I use different collapse_key for different message and I receive all
    of them (of course when the device online). </p>
    
    <blockquote>
      <p>Is anybody knows how can I fix this?</p>
    </blockquote>
  </blockquote>