I got a late payment fee from Klarna for a similar reason. They kept spamming my phone with push notifications, so I revoked their permission to send them. Some time later they weren't able to charge my card and only communicated this by push notication (they had my phone numer, email and postal address). The invoice was something like a week away from being sent for collections when I opened the app by accident and saw it. I go out of my way not to do business with them since then.
They later deleted my account, and had apparently only notified me via SMS using the same marketing account (and no other channels).