Well, this is kinda strange.
You already have a MBA and now you want to go for another masters degree related to your bachelor.
Did you write any statement of purpose explaining why you have chosen this degree despite of already having a masters degree? If not do include this for your next attempt .
Meanwhile, either try to choose another degree or explain to the immigration officer why you are keen to take this degree in your statement of purpose.
~cheers
Bonapart.