Plugin causes a 302 Redirect on some product pages

When I activate the plugin (the premium version of Wholesale Prices) the links to products pages redirect to another empty page.

For example, the following link https://rcore.co/product/the-core-series/ , is redirected to this url: https://rcore.co/?page_id=5, which is an empty page.
When I deactivate the plugin, the problem is resolved.

Any help would be greatly appreciated. Thank you

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