Chmod() and touch() problems with NC 12

Hello, I have these two problems with NC 12 on my server, even though the permissions are set correctly. Thank you for your help, appreciate it.

Error PHP chmod(): Operation not permitted at /srv/www/domain/lib/private/Log/File.php#134
Error PHP touch(): Utime failed: Operation not permitted at /srv/www/domain/lib/private/Files/Storage/Local.php#197

Running on OpenSUSE 42.3 with latest updates.

NC 12.0.4, still the same problem. Does somebody have same experience? How it can be fixed? Thank you for your help;)

Error PHP chmod(): Operation not permitted at /srv/www/domain/lib/private/Log/File.php#134 2017-12-06T18:23:16+0100

Error PHP touch(): Utime failed: Operation not permitted at /srv/www/domain/lib/private/Files/Storage/Local.php#197 2017-12-06T18:23:14+0100