Insecure URL error

I have just installed the Photofocus theme and since doing so it has rendered my domain insecure. On checking, this was the error reported: A file with an insecure url of "http://0.0.0.1/" was loaded on line: 548 of https://www.six4.co.uk/. This URL will need to be updated to use a secure URL for your padlock to return. I have the latest version of the Theme and all my site is up to date. Please advise how to resolve this issue please.