Calorie intake help!

Myfitnesspal has me eating 1200 calories a day, which is astonishing to me because I am 5'4" and weigh 191. I think this might be why I hit a plateau.. My BMR is 1604 and my TDEE is 2593. From what I understand my body is probably in starvation mode. How do I figure out how many calories my body needs, while making a small deficit to help lose more weight?