MyVestaCP : signatures couldn't be verified because the public key is not available

Question

I have installed MyVestaCP control panel on my server which is running on Debian 10. Today, when I ran the "apt update" command, it gave the following error. How can I fix this error?

Get:6 http://apt.myvestacp.com/buster buster InRelease [2,305 B]                                     

Err:6 http://apt.myvestacp.com/buster buster InRelease

  The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 88807D4B2221338C

Fetched 2,305 B in 1s (2,002 B/s)

Reading package lists... Done

Building dependency tree       

Reading state information... Done

All packages are up to date.

W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://apt.myvestacp.com/buster buster InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 88807D4B2221338C

W: Failed to fetch http://apt.myvestacp.com/buster/dists/buster/InRelease  The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 88807D4B2221338C

W: Some index files failed to download. They have been ignored, or old ones used instead.

Answer 1

I found the solution on the Github page of MyVestaCP. SSH to your server as root and run the following three commands in the given sequence. It should fix the error:

wget https://apt.myvestacp.com/deb_signing.key -O deb_signing.key
sudo apt-key add deb_signing.key
sudo apt-get update