the last 10-15 pounds

Options
okay i seem to be stuck at these last 10-15 pounds im really gunning for 15 more pounds but ill take loosing 10 . anyone have any advice or knowledge as to how long it will take me to loose this ? currently i walk a mile a day (just started this ) and aim to consume >1,200 calories i weigh 138 lbs and am 5'7.5... any advice will help . thanks ! (please dont tell me im not eating enough)