The host name did not match

I install successfully Nextcloud on my Linux Mageia pc, but when I log in to my NAS-address, the message appears:

The host name did not match any of the valid hosts for this certificate.

The option: ā€œTrust this certificateā€ is checked.

The next message is then: Not Found
The requested URL/index.php/login/flow was not found on this server.
Apache/2.2.34 (Debian) Server at Port 443

This link works correct on my Windows computer.