The problem is that either your body gets used to the diet and exercise you’re doing or you are eating too few calories.

Try changing your exercise so instead of running you are swimming, or cycling or whatever, and for a couple of weeks raise your calories a few hundred so they are still below what you use, but not as far.

If this isnt working then perhaps you need to check what you are eating more carefully. Is it good food? or a lot of take aways?
Do you have all the vitamins you need? or are you missing out on some?

I found usually i get bored with whatever exercise im doing within a couple months and naturally just change it to something else. In the 7 months ive been dieting i havnt really hit any major plateaus yet. My diet changes all the time and the exercise.
However being a female i HAVE noticed that i do not loose weight the week prior to menstration, and i will drop twice as much the week after (probably just all water retention).

Again and again I have heard people saying they were eating really low calories and exercising heaps and still not loosing weight, and couldn’t break the plateau. What it comes down to is kidding and lieing to yourself, or not measuring exactly.

Recheck with scales and measuring items the food, and stop counting your exercise calories so high, i have found most HR monitors seriously over estimate the calories used and inaccurate.