I canceled my membership at basefit by sending them an e-mail (as instructed). And three months later, I get a Zahlungsaufforderung.

This is ridiculous. I've dug out my e-mail that requests a membership cancellation and I've re-sent it to every e-mail I've found that belongs to them. I've also publicly requested a cancellation by tagging them in social media.

Tomorrow I'm going directly to the gym I used to go and I'll demand to get the phone number from somebody from the central office.

Question is, am I doing all this in vain? Is there still a chance to get out of this ridiculous situation or I just have to pay them?

Thanks in advance.