Extremely upset with the university

I recently received a letter from UNISA informing me that my exam center has been changed to Richardsbay. During registration I had clearly chosen to write my examinations at Mtuba tuba as my mother lives there and I am very fami**** with the area and this was successfully processed and approved on the 27th of July 2015 ,I then now receive this letter stating otherwise and telling me that they have changed my exam center to Richardsbay, I don't understand how they can change my exam venue to NRB firstly without my consent and even try to impose it on me?! Secondly I am not at all fami**** with the area in Richardsbay Im clueless as to what is where and many other things also the area is not within my reach it is approximately an hour and half away from my mothers house at KwaMsane township and I don't understand how do they expect me to travel there especially when all my papers are in the morning at 08