In addition to a description of the bug you are reporting, please provide:
Device Type: Sony
Device Model: 5 III (XQ-BQ 52)
Device Operating System: Android 13
Diablo Immortal App Version: 3.2.2
The Quest Tracker says that I must speak with Captain Rehm in Westmarch to travel to the Northeast, behind the Tamo Mountains. But there is no such option when I speak with him. I have travelled to any destination that Captain Rehm offers, but without success. The main quest task remains open.
Edit: The issue has been resolved by switching the difficulty back to normal.