Lower Back Fat or Muffin top
Oh man, back fat sucks. So hard to burn off. You'll have to be pretty patient with results from there. You can't target fat loss either, and that's the last place it will come off.
Caloric defecit, clean eating, intense training.
Acaloriecounter.com check it out. It will definitely help guide you in the right direction.
6 Months of working out is still very new, I say keep up hard work and watch nutrition in another 6 months the back fat will disappear.
Check out some of my liked workouts I have many that deal with abs. Good luck.