Auto select Product Field using URL Parameters

I am trying to make the button auto-selected using a specific link. The idea is that when a user enters on this link, it will go to a product page but with a specific product variation displayed.

For example, a link would be like: example.com/product1/?attribute_group=4%20Group. It would proceed to the product1 page but 4 GROUP attribute/variation is already selected.

One of the WordPress E-commerce websites I am working on works fine when I try to search for this url with specific parameters. However, the other don’t work with this parameter(bellissimocoffee.com.au). Am i missing something in the functions.php file of wordpress or some script code?

The website working with these query string parameters is > https://brewsolutions.com.au/shop/coffee-machines/la-marzocco-machines/fb80/. If I search for this specific link > https://brewsolutions.com.au/shop/coffee-machines/la-marzocco-machines/fb80/?attribute_group=2%20Group it automatically selects the 2 Group variation. However, on this website (bellissimocoffee.com.au), when I use query strings, it doesn’t auto-select the product variations. Such as https://bellissimocoffee.com.au/shop/region/africa/ethiopia-shakiso-guji/?attribute_pa_size=450g, it doesn’t auto-select 450g in Size dropdown.

I expect that the button will be auto-selected just by searching the specific URL including query string parameters.

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