title: Paypal Payment transaction failed in Magento
body: <p>I have developed a site few months ago but I am having an issue with paypal Express Checkout
  It's giving me this error. this issue arising sometime not all time.</p>
  
  <p>Payment transaction failed. 
  Reason
  PayPal gateway has rejected request. Express Checkout token is missing (#10408:
  Express Checkout token is missing). Express Checkout PayerID is missing (#10419:
  Express Checkout PayerID is missing). The PayerID value is invalid (#10406:
  Transaction refused because of an invalid argument. See additional error messages</p>
  
  <p>Thanks in advance.
  Shivam</p>