Traveler on Android device and Thread running

The android client on the device is 9 and the Domino server,Travler are v9

When we check for traveler status, we sometimes see the below message, and the user device does not synch.

User CN=abc/o=domain on thread DS-16c0[XX][UNID] has been running for 50 minutes

The overall status of the traveler is Red. This is happening only with android devices.

Subject: RE: Traveler on Android device and Thread running

It depends on what the DS (device sync) thread is doing. Most often this is an document specific issue or connectivity to the mail server. You should open a PMR so that we (IBM) can see all of that information and give you a better answer.