A refund is no longer possible due to the acceptance of the terms and conditions upon activation of the services:

The user acknowledges that the service is provided without commitment and that they may stop using it at any time. At the same time, the user expressly agrees that the provision of the service will begin immediately after payment and confirms that, by giving this consent, they waive their right to withdraw from the contract pursuant to Section 1837(l) of the Civil Code. As the service is thereby provided in full, the amount paid is non-refundable.