Welcome,
Not sure why this would happen in release only, but this is unusual:
the app seems to hang right I call startListeningWithLanguageModel several times
It’s unlikely to be necessary to call startListeningWithLanguageModel many times. The usual app design would have it called once and to control whether recognition is being performed with suspend and resume rather than startListening and stopListening. Is there an app requirement that leads to calling it repeatedly?