Terms show a name but no domain or status.
Their domain or status was deleted, or lists were imported after the terms. Restore or re-import the lists, then rebuild the index.
A newly labelled page is not in the glossary.
Confluence takes a few minutes to index a new label. If it is still missing after that, rebuild.
A deleted term is still listed.
The hourly check has not run yet. Rebuild the index to remove it now.
Someone cannot change a status.
They are not in the group set for that step on the Reviewers tab. Add them to the group, or clear the group to let any editor make that move.
The glossary shows an error instead of terms.
That is a real fault, not an empty glossary — the message says what went wrong. Rebuild first; if it persists, send the exact message to support.
Someone sees fewer terms than a colleague.
That is correct. People only see terms in spaces they have access to.