App crashing when I download courses for offline

Memrise Bug Control iOS Bugs
1

Hi! I have a problem with your program. When I want to download course for using them offline, your program crashes.

  1. Course`s URL https://www.memrise.com/course/340/suomen-mestari-1-chapters-1-to-6/ (1200 items).
  2. IPhone X 12.1.3
  3. 40 GB free on device.
  4. Internet connect is 200 mb/s
  5. Use WiFi to download course.
    What I tryed to do:
  6. Delete app.
  7. Reset device.
  8. Download app.
  9. Install app.
  10. Try to download course.
    Nothing help.

Please, fix the bug.