I have this bug in multiple reports where when you export a table less than half of the rows are actually included in the excel file. it looks I'm not the only one who's experienced this. I see simil...
I had this same issue, but I realized what was happening in my case. The table I made in the Power BI visual had limited columns, and some rows appeared to be duplicates on the visual. The COUNT function was working correctly (i.e. counting the duplicates), but only unique records were being displayed in the table visual and data export.