Can't display the visual

Hi, Anonymous 

In Power BI, missing data can lead to visualization errors. You can use DAX functions such as IF or COALESCE to handle missing values.

You can refer to the following DAX:

StandardizedName =
SWITCH(
    TRUE(),
    'Connection Table'[Name] = "alternative name of a sub-department1", "regular name for sub-department1",
    'Connection Table'[Name] = "alternative name of a sub-department2", "regular name for sub-department2",
    'Connection Table'[Name] = "alternative name of a sub-department3", "regular name for sub-department3",
    COALESCE('Connection Table'[Name], "Unknown") // Default Case
)

You should also try to avoid many-to-many relationships. You can try to change the relationship between Connection Table and Overall Department Table to one-to-many. If you cannot change it directly, consider creating an intermediate table to simplify the relationship.

I hope my suggestions give you good ideas, if you have any more questions, please clarify in a follow-up reply.
Best Regards,
Fen Ling,
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