@nicoduck @Ursalzona
I`m not sure if it falls in the jurisdiction of the Bundesnetzagentur (BnetzA), but you can at leat try to open a ticket with them:
https://www.bundesnetzagentur.de/_tools/VSTK/Form01Beschwerde/Sonstiges/jsp.html
You can also start a Privacy enquiry with Hetzner, based on Article 15 GDPR by requesting information about the personal data, they store and process about you as a person. That might give you some indication about the case. For that you can send an E-Mail to data-protection@hetzner.com
@nicoduck @Ursalzona
If they do not give you information about your personal data within 30 days, you can escalate the case to the bavarian Privacy (BayLDA), which is the supervisory authority for Hetzner.
If they try to deny your access request, the BayLDA is also the next step of escalation.
In both cases you can start the enquiry at https://www.lda.bayern.de/de/beschwerde.html