Ive lost my nectar card left it in sainsburys whose policy is to destroy after 24 hrs

This is what Nectar says.

Simply fill in our form on the link below and we'll pop a new card or key tag in the post for you. It'll be with you within ten days. If your card's damaged, you can continue using the same Nectar card number. If it's lost or stolen, we'll give you anew card number straightaway.