What am i doing wrong?

Hi everyone

So basically ive lost 100 pounds got another 70 to lose. Past 4 months i aint lost a pound but i aint gained either. I eat between 1200 and 1500 calories a day i walk 3 miles a day, do 3 aqua classes a week and i cycle 6 miles a day on my exercise bike. Ive started doing curves in the morning and i still aint losing :sad: . So i think i do enough exercise so it must be my diet? Im starting to get really frustrated and angry i aint losing anymore weight. So any suggestions?

Cheers

Dawn