Bug Description

Hello,
I follow the tutorial examples (https://github.com/topoteretes/cognee/blob/main/examples/python/ontology_demo_example.py) to include an ontology.
When I want to visualize the graph (either by using await visualize_graph() or by creating the html directly), I noticed that the graph's nodes have not labels.
Please see picture attached.

Chrome and Safari give the same result.

Thanks for any help.

Steps to Reproduce

1. run example: https://github.com/topoteretes/cognee/blob/main/examples/python/ontology_demo_example.py

Expected Behavior

for example: https://www.cognee.ai/blog/deep-dives/ontology-ai-memory
nodes have labels

Actual Behavior

nodes do not have labels

Environment

python 3.12
cognee 0.4.0
macOS 15.6.1
Chrome Version 142.0.7444.135 (Official Build) (arm64)

Logs/Error Messages

Additional Context

No response

Pre-submission Checklist

• I have searched existing issues to ensure this bug hasn't been reported already
• I have provided a clear and detailed description of the bug
• I have included steps to reproduce the issue
• I have included my environment details