Missing Template "layout/theme.liquid"

I’ve just purchased a theme template and when I try to install it on Shopify i get the following errors:

zip does not contain a valid theme. missing template : liquid/theme.liquid

Picksy - React Gatsby Grocery Ecommerce Template

Make sure you have purchased the “Shopify” version of the template. If you purchased “HTML” or “WordPress” version of the template and trying to upload it to Shopify, it won’t work and you would get the same error message.

It sounds like this is an HTML template “Picksy - React Gatsby Grocery Ecommerce Template”