When you need to use the measure, You need to hide the implicit measures that you create, for example, aggregate functions are automatically generated in your tables, as shown in the following figure
If you have created a measure that is summed, you need to hide the implicit measure
Then the measure will display, please check that if you have the implicit measures, you can refer to the following video.
Where's my measure??? (Power BI Paginated) - Bing video
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