Shopify has a limitation which blocks the extension from identifying the Company and Street2 address fields correctly from the order detail page. To circumvent this simply click the Edit link next to the shipping address. An edit form will pop up. Once the popup is visible open the MyParcel.com Chrome extension by clicking the icon in the top right of your browser. The extension will now recognise all fields correctly.
We are actively working on this issue and hoping to address it soon in a future update of the Chrome extension.