FNB falling apart?

After years of good service, FNB services are simply not working for me anymore. I have tried to change my address for 6 months without success. They say is is done, but then my statement shows the old address again and again. I have been trying to get a letter which will enable me to get a refund from a travel agent for over a month without success. The FNB help system is completely useless. and I feel completely helpless having wasted endless hours using all the support options - including going into the branch. PLEASE HELP