iFrame problem

Hi, I hope someone can help

I have created a shop with Woo-commerce and WC-marketplace, (https://market.online-trader.co.za) when I go directly to the site and click on any page even with a short code it works perfectly and shows, one can go through the entire process and checkout, however I have pulled the entire site into my main website with an iFrame, (https://www.online-trader.co.za/index.php/online-shop) all the pages work and show except for the pages with short-codes on, nothing appears. The pages login/register, checkout etc doesn’t show, just a blank page. The moment you put a short-code on a page it shows on the direct site, but on the site with the iFrame it disappears.

I have disabled all the plugins, (except woocommerce and wc) as well as tried different themes, still the same result. I do have the woocommerce shortcodes plugin installed as well.

Does anyone have any suggestions please, I will really appreciate it.
Andre

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