The following signatures couldn't be verified because the public key is not available: NO_PUBKEY B53DC80D13EDEF05

[dyrnq]

apt update

Err:4 https://mirrors.tencent.com/kubernetes/apt kubernetes-xenial InRelease
  The following signatures couldn't be verified because the public key is not available: NO_PUBKEY B53DC80D13EDEF05

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.tencent.com/kubernetes/apt kubernetes-xenial InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY B53DC80D13EDEF05
W: Failed to fetch https://mirrors.tencent.com/kubernetes/apt/dists/kubernetes-xenial/InRelease  The following signatures couldn't be verified because the public key is not available: NO_PUBKEY B53DC80D13EDEF05
W: Some index files failed to download. They have been ignored, or old ones used instead.

apt update

Err:6 https://mirrors.aliyun.com/kubernetes/apt kubernetes-xenial InRelease
  The following signatures couldn't be verified because the public key is not available: NO_PUBKEY B53DC80D13EDEF05

[dyrnq]

xref kubernetes/release#1982

[bigbigbighead]

hey,bro. I just met the same problem as you. Even the pubkey is the same. How did you solve it?