Terrible Customer treatment

Terrible experience at FNB. FNB Northgate has a number of entrances. I entered from the 1st floor banking entrance. Went to the front entrance at the bank & asked where I should queue. They indicated to the left of the bank & I went to the back of the queue. Shortly afterwards security came & let a person queue in front of me. On indicating that the person must go to the back of the queue security informed me that I am not in the line and this person queued at the level below. I have no idea what that meant as I entered on the 1st floor. They then sent a second security guard to remove me from the queue. The bank manager intervened & the security discussed with the customers behind me of the queue if they must remove me as I did not queue from the ground floor. Security acted as if I did something wrong, which I did not. I obviously refused to move from the queue. Nowhere are any signs or was I told I have to stand in a queue from the ground floor. Security is in charge of FNB customers and treats them like second rated citizens & customers that has to bow down to them. Totally unacceptable service & treatment of customers. I have never been treated so badly in my life. This is what happens when there different rules and regulations for different citizens and the rules are not defined for all situations. i.e. 2 entrances but no signage or clear instructions as as well giving incorrect instructions.