The law is a complex matter, and the rules vary from country to country. In France, the seller is responsible until delivery. In case of loss by the carrier, he remains liable (unless you have expressly chosen a means of transport different from that offered by the seller). It seems to be the same rule all over Europe, that is if you buy on the Internet in the European Union.

If you are European (Italian for example...) this link could help you: https://commission.europa.eu/live-work-travel-eu/consumer-rights-and-complaints/resolve-your-consumer-complaint/european-consumer-centres-network-ecc-net_en

'On ne devrait jamais quitter Montauban' (Fernand Naudin).