Zettle POS Integration for WooCommerce

I deleted all variations from a variable product and now it doesn’t show on Zettle anymore. What is wrong?

This is expected behaviour. A variable product without any variations it is not valid for sale in WooCommerce and therefore will not sync to Zettle. In a similar way when you have a variable product and delete its last variations, the product will be removed and disappear from the Zettle library.