After filing a complaint, and thanks to the mediation of Casino Guru, I received a 100% refund of the amount owed. The case stemmed from a "non-closure" after I made my gambling addiction clear. They took a while to agree with me (I'm not going to allege bad faith) but in the end it was resolved, and I think it's fair to acknowledge this fact.
Después de interponer una queja, y gracias a la mediación de Casino Guru, me reintegraron el 100% del importe debido, el caso provenía de un "no cierre" después de dejar clara mi ludopatía, tardaron en darme la razón (no voy a aducir mala fe) pero al final se solucionó, me parece justo reconocer este hecho.