Some pages will not load

I’ve started to get a strange problem and am looking for a solution. Some pages load fine, others with a ‘Oops! Google Chrome could not connect to https://www.jeffreydriver.co.uk’. Has anyone else experienced this?

I’ve tried using different browsers, but the same page(s) seem to be affected. Tried resetting permalinks, and that didn’t help. Currently, this page isn’t loading (https://www.jeffreydriver.co.uk/portfolio/) I’ve tried disabling all plugins, but the problem remains. This has started happening with the latest update.

Initially a different page wasn’t loading (https://www.jeffreydriver.co.uk/full-design-portfolio-and-archive/) so I duplicated the page and pointed links to the new page, however, the problem jumped to another page which I’d just edited (https://www.jeffreydriver.co.uk/portfolio/)

Any help greatly appreciated. Thanks.