Why aren't product variant parameters being respected on my website?

Main product:

https://woowoo.fun/products/woo-woo-tame-it
50ml: 32730451443794 https://woowoo.fun/products/woo-woo-tame-it?variant=32730451443794
100ml: 32732436299858 https://woowoo.fun/products/woo-woo-tame-it?variant=32732436299858

Any idea why both of the variant URLs just land on default?

I’d expect it to preselect the correct variant and price.

This happens on all products with variants.

The only reason I spotted it was that variants with different prices in the Shopify Google channel feed were being rejected in Google Merchant Center because the landing page price doesn’t match what appears in the feed.

That is a theme related issue. I have not seen this issue in over 2 years. I recommend reaching out to the theme developers to update the theme.

Yeah, expected as much. Cheers.