Can’t Customise Tracking Page

Hi, I bought this plugin a day ago and I can’t preview my tracking page to customise it in the backend.

The first image is from your YouTube tutorial which shows we can preview the tracking page and we can see what we’re customising.

But in the second image, when I try to customise it, the tracking page preview with “Delivered”, “Carrier Name” etc is not there which makes it harder for me to visualise what I’m editing.

How can I see the tracking page preview?

Thanks in advance