Has Mixpanel disabled the csv export?

Hi Chenyi! Julianne from Mixpanel Support here. Diving right in, if your role is set as Consumer, you won't be able to download reports in CSV format. Only users with the role of Analyst or higher have the permission to download reports in CSV format. A project Admin or Owner can update your role in the project settings. The Roles & Permissions doc has more information about what each role can do.