Featured Imaages No Longer being imported

The Featured Image for articles in the RSS feed are no longer being added to the post when imported with Echo RSS. This started to happen a couple of days ago, and I am not aware of any changes being made to the plugin configuration. I can see the images in the parent RSS feed (https://businesscrack.co.uk/feed/) and EchoRSS has "Enable Featured Image Importing" ticked for the feed. Any thoughts as to why this should suddenly stop working? Thanks - Stuart