Bad attitude from supervisor!!!

I have been a client of MTN for the past 10 years. In 2011 I moved from prepaid to contract. I have never missed a payment in my 4 years of being on contract. I have been on unpaid maternity leave and hadn't been able to make any payments on my contract. I called 808 on 16/03/2015 to make a payment arrangement and I spoke to a very rude agent. I requested that she transfers me to her supervisor since I couldn't take her attitude and she was 10x worse. I explained to her my situation and she laughed out at me as if it was a big fat joke! When i asked her why she was laughing she said I sounded funny, the manner on which I speak is funny, my voice is funny etc, she continued to insult me till I couldn't take her insults anymore and I told her I would write a complain about her on Hello [URL Removed] she said I can go right ahead. I thin k I can just call MTN and make demands. Is this how you treat your customers MTN?