We have discovered a rare issue that cause wrong manga grouping in Favorite list, manga from one source may be listed under another source.
We are still working on a permanent fix for it. However, we have found a walk-around for this situation:
Tap on the manga and tap back. Favorite list should return back to normal.
Affected version: Android 3.0 and above
First reported date: Sep, 2017
Resolved date: TBA