Random long sustained notes in SeeMusic

So i recorded a MIDI file via perfectpiano from my MIDI keyboard.

then i tried importing this file in the seemusic app, which all worked fine.

then, after playing this MIDI file, ca. 3m in, random notes started sustaining almost infiniteley. i checked the MIDI file and everything was fine and without long sustaining notes, but in the seemusic app random notes appeared.

im using the app on a Samsung Galaxy A8, operating with Android 9.