Solving W: GPG error when updating Kali Linux Repository

Hello, i'm coming back :D
this time i want to write step to solve W: GPG error when updating Kali Linux repository. This usually happen when you install Kali Linux repository to another Debian Linux Distro. The error messages are like this

W: GPG error: http://http.kali.org /kali Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY ED444FF07D8D0BF6 

W: GPG error: http://http.kali.org kali-dev Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY ED444FF07D8D0BF6

So, how to solve it? its simple, you just input this command to your terminal console

gpg --keyserver pgpkeys.mit.edu --recv-key  ED444FF07D8D0BF6
gpg -a --export ED444FF07D8D0BF6 | sudo apt-key add -

replace the yellow text  with the key that was displayed in the error message
and then you must update your repository
done :D

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