Very poor service from FNB

Am SO frustrated with FNB. My credit card should be paid in full each month and only the minimum balance was deducted. Phoned 24 hours ago to complain and nothing has been done. Tried phoning the 087 number again today. Had to wait for ages, got put through to credit card section, had to wait again then got cut off. This is in spite of them having "a queue of bankers ready to assist you". Yeah right. And they had the cheek to ask me to rate their service when they emailed me yesterday with the reference number.