ReactJS error after installing Content Manager

Hi all,

I've recently installed the EPiServer.Labs.ContentManager NuGet package against our EPiServer solution. However, when I view the Content Manager page I am receiving the following JS errors:

Here is the line causing the error:

useEffect(() => {
onReload();
communicator.onSetContentLanguage(defaultLanguage.name); <------------------ Breaking here, defaultLanguage is undefined.
}, []);

I had a look at the CMS settings and seems there should be a default language:

I am wondering if anyone has any ideas how I would go about fixing this?

Note: EPiServer version installed is 11.15.1

Globalization setting in web.config is:

<globalization culture="en-AU" uiCulture="en-GB" requestEncoding="utf-8" responseEncoding="utf-8" resourceProviderFactoryType="EPiServer.Framework.Localization.LocalizationServiceResourceProviderFactory, EPiServer.Framework.AspNet" />