MongoDB Compass Import unrecognized UTF-8 CSV characters even if Excel is displayed correctly

I'm trying to import a CSV file into a MongoDB collection with the help of the Compass tool.
The import was successful, but I have special characters, such as German umlauts, marked with an interrogation point.
The CSV is an Excel export. I have saved in CSV format and selected in Tools-> Web encoding in UTF-8 format. It did not work.