Bdtyktl

I can not refresh my Ubuntu 18.04. It says:

$ sudo apt-get update && sudo apt-get install traceroute

[sudo] password for phantom: 

Ign:1 cdrom://Ubuntu 18.04.1 LTS _Bionic Beaver_ - Release amd64 (20180725) bionic InRelease

Err:2 cdrom://Ubuntu 18.04.1 LTS _Bionic Beaver_ - Release amd64 (20180725) bionic Release

  Please use apt-cdrom to make this CD-ROM recognized by APT. apt-get update cannot be used to add new CD-ROMs

Get:3 http://ftp.kfki.hu/linux/ubuntu bionic InRelease [242 kB]

Get:4 http://ftp.kfki.hu/linux/ubuntu bionic-updates InRelease [88,7 kB]       

Hit:5 http://ppa.launchpad.net/arunsivaraman/gpuviewer/ubuntu bionic InRelease

Get:6 http://ftp.kfki.hu/linux/ubuntu bionic-backports InRelease [74,6 kB]     

Get:7 http://ftp.kfki.hu/linux/ubuntu bionic-security InRelease [83,2 kB]      

Get:8 https://dl.winehq.org/wine-builds/ubuntu bionic InRelease [6.257 B]      

Err:8 https://dl.winehq.org/wine-builds/ubuntu bionic InRelease 

  The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 76F1A20FF987672F



** (appstreamcli:3850): WARNING **: 23:46:05.385: No origin found for file ftp.kfki.hu_linux_ubuntu_dists_bionic-updates_main_dep11_Components-amd64.yml.gz



** (appstreamcli:3850): WARNING **: 23:46:05.729: No origin found for file ftp.kfki.hu_linux_ubuntu_dists_bionic-updates_universe_dep11_Components-amd64.yml.gz



** (appstreamcli:3850): WARNING **: 23:46:05.741: No origin found for file ftp.kfki.hu_linux_ubuntu_dists_bionic-updates_multiverse_dep11_Components-amd64.yml.gz



** (appstreamcli:3850): WARNING **: 23:46:05.741: No origin found for file ftp.kfki.hu_linux_ubuntu_dists_bionic-backports_universe_dep11_Components-amd64.yml.gz



** (appstreamcli:3850): WARNING **: 23:46:05.741: No origin found for file ftp.kfki.hu_linux_ubuntu_dists_bionic-security_main_dep11_Components-amd64.yml.gz



** (appstreamcli:3850): WARNING **: 23:46:05.741: No origin found for file ftp.kfki.hu_linux_ubuntu_dists_bionic-security_universe_dep11_Components-amd64.yml.gz

Reading package lists... Done

E: The repository 'cdrom://Ubuntu 18.04.1 LTS _Bionic Beaver_ - Release amd64 (20180725) bionic Release' does not have a Release file.

N: Updating from such a repository can't be done securely, and is therefore disabled by default.

N: See apt-secure(8) manpage for repository creation and user configuration details.

W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: https://dl.winehq.org/wine-builds/ubuntu bionic InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 76F1A20FF987672F

phantom@phantom-Lenovo-Z50-70:~$ sudo apt-get update && sudo apt-get install traceroute

Ign:1 cdrom://Ubuntu 18.04.1 LTS _Bionic Beaver_ - Release amd64 (20180725) bionic InRelease

Err:2 cdrom://Ubuntu 18.04.1 LTS _Bionic Beaver_ - Release amd64 (20180725) bionic Release

  Please use apt-cdrom to make this CD-ROM recognized by APT. apt-get update cannot be used to add new CD-ROMs

Get:3 http://ftp.kfki.hu/linux/ubuntu bionic InRelease [242 kB]

Get:4 http://ftp.kfki.hu/linux/ubuntu bionic-updates InRelease [88,7 kB]       

Hit:5 http://ppa.launchpad.net/arunsivaraman/gpuviewer/ubuntu bionic InRelease

Get:6 http://ftp.kfki.hu/linux/ubuntu bionic-backports InRelease [74,6 kB]     

Get:7 http://ftp.kfki.hu/linux/ubuntu bionic-security InRelease [83,2 kB]      

Get:8 https://dl.winehq.org/wine-builds/ubuntu bionic InRelease [6.257 B]      

Err:8 https://dl.winehq.org/wine-builds/ubuntu bionic InRelease

  The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 76F1A20FF987672F

Reading package lists... Done

E: The repository 'cdrom://Ubuntu 18.04.1 LTS _Bionic Beaver_ - Release amd64 (20180725) bionic Release' does not have a Release file.

N: Updating from such a repository can't be done securely, and is therefore disabled by default.

N: See apt-secure(8) manpage for repository creation and user configuration details.

W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: https://dl.winehq.org/wine-builds/ubuntu bionic InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 76F1A20FF987672F

I tried to change the server of download, and tried to restore the authentication, but no matter what the latter means, it just didn't work. Is anybody else experiencing something like that?