Rude and unprofessional Service Agent with a lack of Customer Service

The service agent by the name of Janina is rude to say the least. She just shouted at me (the customer) over the phone because I am unhappy with her service. Instead of even taking the time to see my point of view, she is just being defensive and giving me attitude. The way in which she just spoke to me as a customer is very appealing to think that I keep bringing my money to this branch to be met with this kind of service? The car was dropped off on Thursday, 14th December and she gave me a call to approve the cost to which I did. I did not receive a courtesy call at the end of the day to say that the car’s service has been completed. Not knowing the status on the service, we had to be the ones to call them at the end of the day and phones weren’t answered. We called again over the long weekend to follow up only to be told that we can only collect on Monday, 18th December - so essentially an entire long weekend was spent without a car and an update. I reported this to the agent who called me to get feedback on my experience with servicing my car at this branch to which he advised that I will get a call from Janina - only get met by a confrontational call by Janina telling me that when she called me for approval she explained that the car should be collected at 16:30 and she thinks that’s good enough. As if delays don’t happen with services sometimes? As if a customer’s day cannot get busy and it’s too much to ask for a courtesy call to say that the vehicle is ready for collection? This has been the first time taking my car here where a service agent has NOT called me to say the vehicle is ready for collection. She kept interrupting me every time I tried to give her my point of view as a customer and just kept shouting and giving me attitude over the phone. She needs Customer Service training and I can jot guarantee that after 7 years of servicing my vehicle with Williams Hunt Fourways since purchasing it from them in 2016, this will be the last time I bring my vehicle here.