Hi,

The error message you're encountering:TypeError: can only concatenate list (not "NoneType") to list, typically occurs in Odoo when you're importing employee data and one of the fields expected to be a list (such as many2many or many2one relational fields like departments, tags, skills, etc.) is receiving a None value instead. Odoo tries to concatenate that value with an existing list but fails because NoneType isn’t a valid list. This often happens when the import file contains empty cells in a column that's expected to reference related records. To fix this, carefully review the columns in your CSV or Excel file: make sure all relational fields (like department, job position, tags, or country) either have valid existing values or are left completely out of the file if optional. Also, ensure that those fields are correctly matched during import and that no columns are mislabeled or partially filled. Try importing a small batch first to isolate the problematic row.

Hope it helps.