From the images, you created the PivotChart in Excel instead of Power BI desktop, right?
Based on my research, the chart horizontal axis will display labels based on [Blood Type] column values. If you want to display other values which are not in this column, you need to create another column to contains complete blood type.
If you have any question about PivotChart, please post a thread in Power Pivot forum to get dedicated support.
Community Support Team _ Qiuyun Yu
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