Even though this ocurred when activating Woocommerce, first you should contact your Web hosting service for help. Before changing anything further you need to make a copy of the database to save all information.
"I changed the domain from www.lisabauer.ch to www.naza.ch"
"The domain changes immediately to:
https://right.trainresistor.cc/follow/track?457423/wp-admin/"
This "right.trainresistor.cc does this make any sense to you?
Are you able to log into the back-end?
Do you know what version of Lay Theme you were running?
Did you have an out of date Carousel version?
Did you have any suspect Custom JS or <Head> Content?
What Third-party plugins did you have installed? (if any).
If you cannot log into the back-end, I think the first step Lisa is to save a copy of the current database and files. Contact your Webhost about Mysql (for wordpress database) & FTP File manager (Files & Wordpress Theme Content etc).
Talk soon & best wishes 🌻 Richard