[ID-43]Fix "start_date" and "end_date"

Description

Fix "start_date" and "end_date"

**Resolves #43

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[x] Bug fix (non-breaking change which fixes an issue).
[ ] New feature (non-breaking change which adds functionality).
[ ] Breaking change (fix or feature that would cause existing functionality to not work as expected).
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[ ] My change requires updating the documentation.
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[ ] Any dependent changes have been merged and published in downstream modules.