Factual errors.
WHY IT HAPPENS
It generates plausible text. Plausible and true are different properties.
Where it lacks information, plausible text is still produced.
WHAT TO DO IMMEDIATELY
Tell it, with the correction.
"That is wrong. [Correct information]. Redo it with that."
IF IT REPEATS THE ERROR
Start a new conversation.
The wrong information is in the context and keeps influencing everything after it.
WHAT NOT TO DO
Ask whether it is sure. It asserts confidence either way. Assume the corrected version is now accurate throughout.
WHAT TO CHECK AFTERWARDS
Everything else in the output. One error suggests others.
IF YOU PUBLISHED IT
Correct it promptly and note the correction.
Then check other content produced the same way.
THE PREVENTION
Supply the facts yourself. Use it for language, not for information.
Verify anything specific before publishing.