This connection is not private

Hi,
I would like to upgrade to PRO version but I noticed that if you try to access my website by typing “www.youngprinters.co.za” it will show a warning that says “This connection is not private” but if you type “https://youngprinters.co.za OR youngprinters.co.za” it will open.

Does it mean that my website cannot be opened with “www”? and it happens especially on smartphones.

Thanks

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