apt update gets error

[chinaliuxiaojun99]

ubuntu 24.04 LTS
sudo apt update

Reading state information... Done
106 packages can be upgraded. Run 'apt list --upgradable' to see them.
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: https://mirrors.aliyun.com/postgresql/repos/apt noble-pgdg InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 7FCC7D46ACCC4CF8
W: GPG error: https://repo.pigsty.cc/apt/infra generic InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY E7935D8DB9BD8B20
W: GPG error: https://repo.pigsty.cc/apt/pgsql/noble noble InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY E7935D8DB9BD8B20
W: Failed to fetch https://mirrors.aliyun.com/postgresql/repos/apt/dists/noble-pgdg/InRelease The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 7FCC7D46ACCC4CF8
W: Some index files failed to download. They have been ignored, or old ones used instead.
N: Missing Signed-By in the sources.list(5) entry for 'https://mirrors.aliyun.com/ubuntu'
N: Missing Signed-By in the sources.list(5) entry for 'https://mirrors.aliyun.com/ubuntu'
lucky@dev:~$ grep aliyun.com -r /etc/apt

[Vonng]

well we skip public key validatation to avoid add keys to your system. It should be a warning rather than error.