Worst customer service ever

Worst customer service ever.

I'm was on a sleepliner bus to Pretoria from Port Elizabeth, the bus stopped at bloemfotein. Being pressed I quickly went to the station intercape office toilet upon my return. The driver put someone else on my seat. I went to the driver to get a explanation. He rudely told to go get any seat. I was sitting with my family we bought 8 tickets. I would have gotten my son to go upstairs but he howled at me to carry the child. My kids payed and I could not be expected to carry a 6 year all that way at night. I called customer services line. The lady took my ticket number and said she'll call the drivers. To put salt on the wound the other driver came found me standing and walked away. I'm still in shock that they just take money without counting the passengers. What are seat numbers for and are we bags of potatoes that can be piled. All seats had people even upstairs. I was told to lodge a complaint by email what about now nothing was said nor done.