Some advisories in the repository do not have a "published" field.
Sample Reference:
PYSEC-2024-154

Some advisories missing the "published" field include:
PYSEC-2023-174
PYSEC-2023-175
PYSEC-2023-181
PYSEC-2023-182
PYSEC-2023-183
PYSEC-2023-184
PYSEC-2023-238
PYSEC-2024-1
PYSEC-2024-152
PYSEC-2024-55
Please check this and get back once resolved.