Configurable variation is unidentifiable – Magento 2.3.1

I’m getting the Configurable variation is unidentifiable error when trying to import the configurable items to Magento 2.3.1.

I think I have the correct format for the csv, using the defined format,

configurable_variations sku=WAL-WM-03-BLA-UNI,color=Negro,size=UNI|sku=WAL-WM-03-GOL-UNI,color=Dorado,size=UNI|  configurable_variation_labels color=Color,size=Size 

Any ideas?