During upgrade hit error
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: https://packages.gitlab.com/gitlab/gitlab-ce/ubuntu 7 focal InRelease: The following signatures were invalid: EXPKEYSIG 3F01618A51312F3F GitLab B.V. (package repository signing key) packages@gitlab.com
W: Failed to fetch https://packages.gitlab.com/gitlab/gitlab-ce/ubuntu/dists/focal/InRelease 3 The following signatures were invalid: EXPKEYSIG 3F01618A51312F3F GitLab B.V. (package repository signing key) packages@gitlab.com
W: Some index files failed to download. They have been ignored, or old ones used instead.
Answer:
Delete old gpg-key
curl -s https://packages.gitlab.com/gpg.key | apt-key add – ; apt-get update