Forum Discussion
Regional settings
Doing some searches on this site, it appears Power BI struggles with hierarchy language when the regional language is changed midway through it's existence.
Two options.
1. Rebuild from scratch with English as the Power BI language at the start.
2. Manually create columns in Power Query to define the English month name based on the date information.
This post https://community.powerbi.com/t5/Desktop/How-to-change-language-of-date-hierarchy-field/m-p/1365507#M584517 has an example of a user who struggled with this too and ended up doing the manual route, hopefully that may help.
You might have a step on the Power Query loading of the data table that setting the locale to French.
https://www.myonlinetraininghub.com/change-type-using-locale-with-power-query This url has some good information that may help you either find where it's happening in Power Query (Transform Data) or to manually add a step to convert the month names into English.