FNB CREDIT CARD DIVISION REALLY BAD BAD SERVICE

I am so sick and tired of FNB Credit Card division this is not the first time I have had an issue with this division, I rang them last month to ask why and who gave them the authority to just change my debit order date for my payments on my card as I only ever get paid on the very last working day of every month, the first lady I spoke to was so rude that she even put the phone down on me and I had to call back again, the second person I spoke to she just could not care about me or my problems and politely told me that I would need to change the date myself, I asked why must I change the date back when your division changed it without permission in the first place, and no response from her she just ignored my question and said that I would need to change the date back there was nothing she could do as my account is now showing as being in arrears, I then said but my account is not in arrears as the the date for payment due is the 1st of every month and not the 25th of the month and eventually she just left me hanging on the phone until I had to put the phone down and call back for a third time which at this point has infuriated me even more but she was more polite and helpful but did not sort my problem out as I am now at the end of May and have just received a message from FNB to say that my credit card account is overdue. FNB where do you get your employees from and who gives FNB the permission just to decide to change my debit order date on my account without consulting me first or is this a scheme by FNB to suck more money that they don't deserve from their customers. I am really annoyed with your service and think you should send your customer service ladies in your credit card division for further customer service training as the ones i have dealt with really need a kick up the butt for being so rude and unhelpful. you don't deserve any stars I am forced to put a star here or I cant write my review. FNB credit card division get your act together or employee people who actually want to work and appreciate doing their job.