Contact form 7 in Chinese language not showing in https but shows in http

Hi,

I have a site which uses some pages translated into Chinese and one of those pages is a secure membership form: https://newcastle.amieu.asn.au/membership-application-direct-debit-authority/

The same form has been translated into Chinese, however, when I tick the “secure this page” box like I have done with the English one, the page will not view at all. When unticked it views properly in http.

Chinese page: https://newcastle.amieu.asn.au/%E4%BC%9A%E5%91%98%E7%94%B3%E8%AF%B7%E8%A1%A8%E5%8F%8A%E9%93%B6%E8%A1%8C%E8%BD%AC%E5%B8%90%E6%8E%88%E6%9D%83/

Any solution to this?
Thanks,
Louise

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