Report to the .swiss registry any detected abuse concerning a .swiss domain name, such as, in particular, cases of use of an illicit nature, contrary to public order or to the .swiss registration rules. Cases of spamming, phishing, bootnets and malware can also be reported.

domainnames@bakom.admin.ch

dot.swiss
Federal Office of Communications OFCOM
Case postale 252
2501 Biel-Bienne

https://www.nic.swiss/content/nic/en/home/report-abuse.html