DynamoDB - Key element does not match the schema
<p>I'm trying to update an Item in my Dynamodb Table +Users+. I have tried many different ways but I always received the same error message: </p>

<blockquote>
  <p>The provided key element does not match the schema</p>
</blockquote>

<p>The creation of an Item works, as well as a query but not the update. When I check on DynamoDB the user is well created:</p>

<pre><code>{
  "email": "test@email.com",
  "password": "123",
  "registration": 1460136902241,
  "verified": false
}
</code></pre>

<p><strong>Here is the table information</strong>:</p>

<ul>
<li><strong>Table name</strong>: Users</li>
<li><strong>Primary partition key</strong>:   email (String)</li>
<li><strong>Primary sort key</strong>: registration (Number)</li>
</ul>

<p><strong>Here is the code (called from lambda):</strong></p>

<pre><code>exports.handler = function(event, context)
{
    var AWS = require("aws-sdk");


    var docClient = new AWS.DynamoDB.DocumentClient();

    var params = {
        TableName: "Users",
        Item:{
            email: "test@email.com",
            password: "123",
            verified: false,
            registration: (new Date()).getTime(),
        }
    };

    // Create the user.

    docClient.put(params, function(err, data)
    {
        if (err)
        {
            context.fail("Put failed...");
            return;
        }

        var params = {
            TableName: "Users",
            Key: { email : "test@email.com" },
            AttributeUpdates: {
                verified: {
                    Action: "PUT",
                    Value: true
                }
            }
        };

        // Update the user.
        docClient.update(params, function(err, data)
        {
            if (err)
            {
                console.log(JSON.stringify(err));
                context.fail(JSON.stringify(err));
                return;
            }
            context.succeed("User successfully updated.");
        });


    });

};
</code></pre>

<p>Do you have any idea of what could be wrong in my code? </p>