My Limit

I have had my credit card for over 20 years and every month I trf my salary, maintenance and any other money I get to my credit card acc to save on interest and use the card when I need to to earn ebucks I hardly use my cheque account. I received a rental about which I didn't want to use and trf it to my credit card until I need it. Well card division with out a word just went and reduced my limit from R60k to 37k taking my whole rent amount, putting me in a big predicament financially, this is not one how can they do this to their clients, banks are not longer her to help clients but to do the complete opposite! I have send them an email last week and still I have not had a response!! Disgusting FNB