Something not working?
Duru is run by one person, not a support department. Write and you will get a real answer, usually within a day or two.
An import produced nothing, or the wrong thing
Send the file and the course name. Extraction is a model reading your pages, and a layout it handles badly is worth seeing.
Delete your account, or download everything
Both are in the app under Account. Deleting removes your courses, cards and schedule, and first cancels a subscription bought on the web or on Android. One bought on iPhone has to be cancelled in the iPhone's Settings — Apple lets nobody else do it.
Change or cancel a plan
On the web: Account, then Plan. Bought in the app: in your phone's subscriptions — on iPhone, Settings, your name, Subscriptions; on Android, Google Play, Payments & subscriptions. Cancelling leaves you on the free plan and keeps everything you have imported.
The tutor will not connect
It needs a microphone permission and a network that allows a live audio connection. If it still fails, say which language and roughly when, and it can be found in the logs.