Stop Showing Default Attribute Variation Selector

I have a product importing plugin which itself has an attribute variation showing option which is way better than the default WooCommerce attribute variation drop down menu. But the problem is, that plugin couldn’t stop default variation drop down menu to be shown. It just shows it’s attribute variation boxes above the default drop down menu. You can see this here: https://shoppinal.com/product/six-claw-crystal-zircon-ring

I want to stop showing this default drop down menu. Seems like I need to add some codes to my Child theme’s function.php file, but I don’t know what.

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