incorrect number plate made

I went to purchase a number plate for my car. The lady refused to let me on as they do not have enough security and there is lot of ****** out there. I was served from outside the burglar door. The lady asked if i wanted a small or big number plate and i told her i wanted a big one. I assumed by the small one she meant the small square one. She told me it will take about 5 minutes so i told them instead of standing outside the burglar door i will wait in the car. She took more than 5 minutes but finally arrived with the plate that was longer than the required size. She then explained that there is a standard long and long which i feel she should have made clear at first. She refused to take responsibility for that or at least meet me half way. She instead expected me to pay another R120-00 for the correct size. I asked for the manager's number and she gave me the office number knowing he was not there. When i realised that i went back and insisted on the cellphone number which she refused but finally gave in. I have since spoken to Ziyad the manager but he gave me the same bad attitude and told me he heard the story and i was the 1 who is wrong and hanged up on me.