Adding labels without replace all labels param fails

[askalski85]

Error

AttributeError: 'Bunch' object has no attribute 'metadata'

Confluence version

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Input md

---
labels:
- label1
---

Command

md2cf --debug \
  --page-id "$PAGE_ID" \
  --title "$PAGE_TITLE" \
  --parent-id "$PARENT_ID" \
  input.md

Adding --replace-all-labels fixes the problem, but makes the parameter obsolete if it does not work without. The mentioned confluence version payload apparently does not include the metadata property even if labels are already defined.