[Koha] Amazon contents not appearing in OPAC

I have been trying to set Amazon cover images/reviews in my koha 3.00.06 installation. I have done settings in Global System Preferences - Admin (AmazonCover Image, Amazon enabled, Amazon Reviews, OPAC Amazon Enabled)=on,Enhanced Contents(AmazonSimilar Items, AWSAccessKey ID, AWSPrivateKey, OPAC AmazonCover Image, OPAC Amazon Similar Item)=on plus added both accesskey and privatekey from AWS, Local Use (Amazon Cover Images, Amazon Enabled, Amazon Reviews, OPAC Amazon Enabled)=on I have also set our system time but still amazon cover images, amazon reviews etc. does not appear neither on staff client as well as on OPAC. Can someone help me to know what is missing here. Thanks, Sunita Barve