MFP vs. scale maintenance calories

avafrisbee

So I have one of those scales that calculates body fat % muscle % (then tells you in kg. how much muscle is in your body) % water bla bla bla.

With a sedentary life-style using the equation BMR*1.2= maintenance calories MFP says my BMR is 1621 so x1.2 equals 1945 (roughly)

My scale with the same input says maintenance is 2029. Why is there a difference and which one should I listen to? I am using the lower of the two. And am I going crazy over "ONLY" 84 calories? I mean that's a whole serving of spaghetti bolognese sauce.