Overview:
When adding an object field to Display in default lists and hovercards, it does not get added as a column.
Root Cause:
This can happen if the user customizes the object records view. For example, if the user resizes columns, or removes or adds columns, it is considered custom.
Solution:
The user has to manually add the field as a column using the Action menu. This is the Action menu located at the top-right when viewing object records:
Related Documentation:
Vault Help Documentation: Configuring Vault Objects
Thank you