title: .save() is not a Function in sequelize
body: <p>I've got &quot;user.save is not a function&quot; error when I try to run these code. I don't know why. I'll happy if you figure out that.</p>
  <pre><code>let updateUserInfo = (data) =&gt; {
      return new Promise(async (resolve, reject) =&gt; {
          try {
              const user = await db.User.findOne({
                  where: { id: data.id }
              })
  
              if (user) {
                  user.first_name = data.first_name;
                  user.last_name = data.last_name;
                  user.email = data.email;
  
                  await user.save();
                  resolve();
              }
              else {
                  resolve();
              }
          } catch (e) {
              reject(e)
          }
      })
  }
  </code></pre>