I changed that link (added -smartphone) after creating this post to see if that would correct the issue.
How do I fix the www issue?
At first, make sure that both config.local.php and store-front settings have www.
Yes, both have the www. at the start. However, in the config I noticed https_path is empty - should this have www.digitalsave.co.uk as well? [url=https://postimg.org/image/zahjazgyf/][/url]
You might also want to search the DB (cscart_seo_redirects) and see if there are any 'src' values that match the SEO names that don't redirect properly.