Kali Linux problem with update solution

If you want to update your system with apt update command and end up with following error:

Pobieranie:1 http://kali.koyanet.lv/kali kali-rolling InRelease [30,5 kB]
Błąd:1 http://kali.koyanet.lv/kali kali-rolling InRelease
  Następujące podpisy były błędne: EXPKEYSIG ED444FF07D8D0BF6 Kali Linux Repository 
Czytanie list pakietów... Gotowe
W: Błąd GPG: http://kali.koyanet.lv/kali kali-rolling InRelease: Następujące podpisy były błędne: EXPKEYSIG ED444FF07D8D0BF6 Kali Linux Repository 
E: The repository 'http://http.kali.org/kali kali-rolling InRelease' is not signed.
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.

then the solution is to issue following commands: wget https://http.kali.org/kali/pool/main/k/kali-archive-keyring/kali-archive-keyring_2018.1_all.deb
apt install ./kali-archive-keyring_2018.1_all.deb