Test URL nor working

Hi, I have just intalled the plugin, when I try to test with the default URL it does not respond, it gives back an error.

Default URL: https://booking.oganro.com/reservation/searchresult!callmdb.html

I have added [ogn_rw_widget_screen] short code to load the widget, it loads, but the problem is the response from the URL.

Please advise.

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