Why does the cart add the default variant instead of the selected one?

This usually happens when the theme’s variant picker is not properly enabled or connected.

Our app works on top of Shopify’s native variant configuration, not independently. This means the theme’s variant picker must be active so Shopify knows which variant is currently selected.

How to fix this:

1

Go to Online Store → Themes → Edit theme

2

Open the Product template

3

In the Product information section:

• Add the theme’s Variant Picker

• Add the OPTIS app block as well

Once the variant picker is enabled, the selected variant will:

• Stay in sync when customers change variants

• Be correctly added to cart instead of reverting to the default variant

👉 Important notes:

• OPTIS restyles and enhances Shopify variants - it does not create a separate variant system.

• The theme’s variant picker must remain enabled for image switching to work properly.

• If you see both the theme variants and OPTIS swatches showing at the same time, this is usually a theme conflict. In that case, please contact our support team and we’ll help resolve it.

After enabling the variant picker, kindly double-check the product page. If the issue still persists, feel free to reach out - we’re happy to assist further.