If purchases from affiliates do extend the life of your Lifemiles, then be aware that a purchase at Farmatodo in Gran Estación qualifies.

You have to have a physical Lifemiles card and have a PIN for it, you then need to activate it for debits and credits in your Lifemiles account.

You then undertake your transaction as normal and then they do a second transaction with a different machine. It is quite convoluted.

It then shows up as below