title: cannot read property to String of undefined [sequelize db:migrate node.js postgres]
body: <p>I run </p>
  
  <pre><code>$ sequelize db:migrate, 
  </code></pre>
  
  <p>but I get this result, with an ERROR </p>
  
  <pre><code>Loaded Configuration file "db\config\config.json".
  Using environment "development".
  ==20190927081141-add-email-to-contacts: migrating =======
  
  ERROR: Cannot read property 'toString' of undefined
  </code></pre>
  
  <p>This is my current config.json file, but I don't have any toString property in it. </p>
  
  <pre><code>//config.json
  
  {
    "development": {
      "port":5432,
      "username": "postgres",
      "password": null,
      "database": "address-bloc-dev",
      "host": "127.0.0.1",
      "dialect": "postgres",
      "logging":false
    },
    "test": {
      "username": "postgres",
      "password": null,
      "database": "address-bloc-test",
      "host": "127.0.0.1",
      "dialect": "postgres",
      "logging": false
    }
  }
  </code></pre>
  
  <p>Here is also the add email to contacts.js file</p>
  
  <pre><code>'use strict';
  module.exports = {
    up: (queryInterface, Sequelize) =&gt; {
      return queryInterface.addColumn('Contacts', 'email',
       {
        email: {
            type: Sequelize.STRING,
        }
      });
    },
    down: (queryInterface, Sequelize) =&gt; {
      return queryInterface.removeColumn('Contacts', 'email');
    }
  };
  </code></pre>
  
  <p>What am I doing wrong? I'm struggling in figuring it out. </p>
  
  <p>Thank you</p>
  
  <p>Federico</p>