Article L133-18 of the French Monetary and Financial Code
In the event of an unauthorised payment transaction reported by the payment service user under the conditions set out in Article L. 133-24, the payer’s payment service provider shall reimburse the payer the amount of the unauthorised transaction immediately after becoming aware of the transaction or after being informed of it, and in any event no later than the end of the first following business day, unless it has good…