To troubleshoot:
Check the source data to ensure that the expected values are present.
Inspect any filters applied to the matrix or the report/page.
Examine any DAX formulas or custom expressions used in the matrix.
Play around with the formatting options to see if it's a visual display issue.
Check interactions with other visuals on the report.
Validate the relationships in the data model.
If you provide more specific details about the matrix configuration, DAX formulas used, or other relevant settings, I might be able to offer more targeted advice.
