GOOGLE REJECS PRODUCTS because there is no price in the structured data

An employee of Google said my products were being rejected in the Google Merchant Center because: “The price in the structured data for the products is 0 euros”.
I have no idea what see means, and she said I needed to ask a developer. She did talk about that they had a tool to see this information but did not want to share the name of this tool.

I did found via: https://search.google.com/test/rich-results and with a product page of mine I got:
“offers”:[{“@type”:”Offer”,”price”:”0.00“,”priceValidUntil”:””,”priceCurrency”:”EUR”,”priceSpecification”:{“@type”:”PriceSpecification”,”price”:”0.00“,”priceCurrency”:”EUR”,”valueAddedTaxIncluded”:”true”}
Maybe see means this?

This product is a variable product with 10 variations in 2 layers, size and color.
So:
Size 1 in blue
Size 1 in red
Size 2 in blue
Size 2 in red
Etc.
Each variation has a regular price and a sale price.

A simple product of mine with no variations got me:
“offers”:[{“@type”:”Offer”,”price”:”0.00″,“priceValidUntil”:””,”priceCurrency”:”EUR”,”priceSpecification”:{“@type”:”PriceSpecification”,“price”:”1299.00″,“priceCurrency”:”EUR”,”valueAddedTaxIncluded”:”true”}

So how do I get both prices in the structured data?

Greetings!