in those situations, especially if the business is unresponsive, i just keep charging back until they stop. if i can subscribe easily, i should be able to cancel just as easily :)
Which bank? My main bank (I'm also in Spain) is BBVA which is able to do charge backs with my debit cards as well. Was possible with Banc Sabadell I used to have as well, really strange to hear there is a bank that doesn't support that today with debit cards.
Debit cards can do chargebacks just as credit cards can do. That's a feature of Visa and Mastercard (and others). If your bank refuses, complain to the card network. Oh and consider changing banks, that's really unacceptable in 2026 and shows an anti customer stance.