Functionality changed after update

Hi there, after updating ShopWP Pro the add to cart functionality has been replaced by a link to shopify after update, how can I get this to work the way it used to? Client is using ShopWP for the sole purpose of connecting the Shopify and WP sites

Original version (the drop down just elects between different buy buttons)

And this is how it looks after update – it seems to take the user off site now.

Can you help here, who can I do to get the functionality back?

Thanks

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