I understand you're looking for an Android 9.0 (Pie) update for your Samsung Galaxy J2 Prime. However, I need to give you an important piece of information first:
The device launched with Android 6.0 Marshmallow and only received an official update to Android 7.0 Nougat. There is no legitimate Samsung firmware for Android 9.0 on this model. samsung j2 prime update 9.0 download