title: react-native-sodium with PHP's sodium fails at crypto_box_seal_open()
body: <p>Here's my encrypting flow:</p>
  <ol>
  <li>I'm creating a key-pair on my iOS device.</li>
  <li>I send to public key to the server (PHP) via Fetch</li>
  <li>I create a push-notification on the server and encrypts it with <strong>sodium_crypto_box_seal()</strong> and sends it sucessfully</li>
  <li>I receive the notification on my iOS device and try unsucessfully to decrypt the message with <strong>crypto_box_seal_open</strong></li>
  </ol>
  <p><strong>React-native:</strong></p>
  <pre><code>import Sodium from 'react-native-sodium';
  let key_pair = { pk, sk } = await Sodium.crypto_box_keypair();
  await sendToServer(pk);
  </code></pre>
  <p>-- PHP --</p>
  <pre><code>$msg = CloudMessage::fromArray(
    [ 'notification' =&gt; $notification,
           &quot;apns&quot; =&gt; [
              &quot;payload&quot; =&gt; [
                  &quot;aps&quot; =&gt; [
                      &quot;sound&quot; =&gt; 'default',
                  ],
              ],
          ]
      ]
  );
  
  sendMulticast( $message, $apn_tokens );
  </code></pre>
  <p><strong>Then back in react-native I receive the push-notification</strong></p>
  <pre><code>const incomingNotifiction = () =&gt; {
  try {
     let note = JSON.parse(notification.notification.body.toString())
     note = btoa(note)
     let result = await Sodium.crypto_box_seal_open(note, public_key, private_key)
  } catch(e) {
     console.log(e) // prints &quot;FAILS HERE!&quot; 
  }
  })
  </code></pre>
  <p><strong>crypto_box_seal_open() from node_modules/react-native-sodium/iOS/RCTSodium.m</strong></p>
  <pre><code>
  else if (crypto_box_seal_open(dm, [dc bytes], dc.length, [dpk bytes], [dsk bytes]) != 0)
      reject(ESODIUM,@&quot;FAILS HERE!&quot;,nil);
  </code></pre>
  <p>Any idea why the decryption fails? Any help will be greatly appreciated. I've struggled for days now</p>