High Payback amounts that exceed my salary

FNB has been kind to me thus far and I haven't had many problem with my student loans. Until this year, I organised that the intrest come off of my own account, and it was switched over. Then all of a sudden R4595.50 gets deducted off of my account in May, I asked that the correct it. I get my money back and this month it happened again. Secondly, this month is the first month I pay capital plus interest and the student loans give me the option over 5 years of R6042 per month! I've asked to please review it and if I cannot pay it back over longer, because that's more than half of my salary. And thus I can pay my medical aid and rent, and nothing more. How do they expect a starting out professional can afford that? I asked multiple times and the question was just avoided. <br> <br> Please can someone help me out? Pay my money back into my account and please give me better options for the payback amount. All which will benefit the bank in anyway.<br> <br> I am at a loss. Two mistakes in two months after I told them to change it. Please FNB, do not lose me as a client.