Hi,

The "Cannot install module 'account_peppol' because an external dependency is not met: phonenumbers" error indicates that the phonenumbers Python library is missing from Odoo's Python environment. Even if you've installed it globally, Odoo uses its own isolated environment.

To fix this, identify Odoo's Python executable (e.g., /path/to/odoo/venv/bin/python) and use it with pip to install phonenumbers (e.g., /path/to/odoo/venv/bin/pip install phonenumbers). Verify the installation and restart the Odoo service. Also, check Odoo user permissions, update pip and setuptools, examine for conflicting packages, verify the module manifest, and clear Odoo's cache. If using Odoo SaaS, contact Odoo Support to install the library.