With this error message Gerrit rejects to push a commit if its commit message footer contains an invalid Change-Id line.
You can see the commit messages for existing commits in the history by doing a git log.
If it was the intention to rework a change and to push a new patch set, find the change in the Gerrit Web UI, copy its Change-Id line and use it to correct the invalid Change-Id line in the commit message of the commit for which the push is failing. How to do this is explained here.
If it was the intention to create a new change in Gerrit simply remove the invalid Change-Id line from the commit message of the commit for which the push is failing. How to do this is explained here. In case you have configured the commit hook a new valid Change-Id will be automatically generated and inserted.