Power BI changes Yes/No values in Excel to True/False
I have an Excel file in Sharepoint that I imported into a Power Bi dataset. The Excel file is actually populated by Microsoft Forms, if that matters. In the Excel file, there are columns with Yes/No values. When creating a pie chart, the values are changed to True/False (see image on left). When adding another value ("Thing" in this case), it shows correctly as seen in the image on the right. I've tried changing the field format in Excel to "Text" and added an apostrophe to the value to no effect.
Previously, I used a streaming dataset and Microsoft Flow to import the data into Power Bi, but the functionality seemed to be incredibly limited. Although, all the modeling/query editor features are still disabled. Therefore, I still can't add custom columns to try manipulate the value.