Cheeky cashier!

Cheeky cashier!
I received a pair of shoes as a gift, the size of which did not suit me.
I therefore leave the office to go get reimbursed at the Galeries Lafayette on Boulevard Haussmann in Paris.
Not having the card which was used for payment (necessarily since it is a gift) I could not be reimbursed.
The insolent cashier could not do anything for me except to offer me a gift card usable only at Galeries Lafayette of course ...
Very bad experience since I had to be absent for half a day from work to make the return trip!