Complain about Customer Service

So on Dec12th at 6:40pm I called Tellus since I had a issue with my billing. Waited for 30min finally got an agent. Unfortunately the agent was very rude to speak. She was very impolite which was not expected  from anyone working at telus or for that matter any company. It seems she was unable to understand me so I asked her to transfer me yo another agent. Again after 30 long mins, I was connected to another agent who seemed to understand  me and resolved  my issue. I do not know if this is the right place to file a complain, if not kindly let me know where I can do it. I would normally  not make a big deal of how agents talk, but she was extremely rude, for her to even assist other customers.