No there was no custom Rom installed. (off the main topic )I even tried rooting my J7 earlier and ended up it saying kernel is not seandroid enforcing. Another wise my J7 works fine.Thank you
Okay so my older brother gave me this phone and he told me it wasn't rooted properly,when I checked for the same every other app said it's not rooted. The lollipop is an official system update OTA. Thank you!