Assalaam, In the same app add feature " Last read" In all categories of Qur'an (e.g. If we read as selective option( Surah, Page,Juz).

Because I noticed this. When we read in our selected option then we have to bookmark the last read ayah. But if we resume from there(Bookmark) It's will continue as Surah not Juz.

Hope this explanation will clear the issue.

Jazaakallahu Khayran.