Rude service

I would like to just complain about the way FNB premier banking call center adviser spoke to me.<br> When i asked why they need to verify my last 6 digits of my card if i can confirm all the rest of my details (I.D address etc?)<br> while im talking i was rudely interrupted saying \can i talk\"? like i'm not giving her as the adviser the chance to talk while im expressing myself as client?<br> Then asked to rather speak to a manger, then i held for over 5 minutes with no one telling me the manager on his why at all and i had to hang up.<br> Then i called again, spoke to a manager Celeste Mans, she advised me i might get in trouble for complaining on social media because our companies all belongs to the First rand Group? <br> So am i then not allowed to express my upset with my bank over social media because coincidentally we work for the same group, although they are banking and we are short term insurance? That can't be acceptable?<br> to whom can i then complain? so must i just leave it in the hands of the company that gave me bad service from the start?"