Very Poor service

Firstly had a sent car in for service received the car and found out that car was jerking. Got the car to Mortimer TOYOTA estcourt in dec 2019 and they found that it was the gearbox. 6 weeks later and paid the enormous amount for the so called"repair" We are still experiencing the problem when taken on along distance. Today 26th january still same.problem. I ask what ever happened to Toyotas professionalism, service quality. The vehicle us in everyday use for my siter ti go to work and back. Mortimer Toyota lacks the ability for total quality service. Totally irritated owner.