I bought a switch for a period of 10 every 100...

I bought a switch for a period of 10 every 100 on the Fnac card
1 week after nothing on the card, I go to the reception and I am told that if I no longer have the receipt they can do nothing for me (while he has the trace of the purchase thanks to the Fnac card in front of your eyes on the computer)

Recommend Amazon, they are at least rulers!