Quit Zalando plus?

I would like to cancel my Zalando plus, do I have to submit a letter for this or does it work as with Netflix at the push of a button?

Does anyone have any experience?

Here you have a guide: https://www.zalando.de/faq/Meine-Vorteile-bei-Zalando-Plus.html. So it works fine. Your Zalando subscription will then be terminated as soon as possible.