Identify the Field Type

• A Selection field in Odoo is used to allow users to choose one option from a predefined list.
• The options are usually static (hardcoded) or dynamically computed.

What Usually Goes Wrong

Common issues with Selection fields include:

• The new value you're trying to assign is not in the list of allowed selections.
• If the field value in the database doesn't match any current selection, it will throw an error.
• When the selection values change in the code but existing records still have old or invalid values, it causes inconsistencies.

Root Cause (Most Likely)

• The value being set or edited is not present in the current list of selection options.
• Odoo checks if the value is valid according to the defined selections.
• If the selection list was changed recently, or if data was imported/created with outdated values, it can lead to this issue.

How to Fix or Avoid It

• Make sure that all values used in your records are present in the current selection list.
• If you modify the selection list, check your database for any existing values that are now invalid.
• You might need to write a script or use the Odoo shell to clean up or update invalid records.

Good Practice

• When changing selection options, migrate existing data accordingly.
• Always validate values before assigning them, especially if they come from user input or external sources.