Reeds Bellvile - Cutomer service BAD

Customer service is very bad. I have an issue and tried contacting the manager, they are always busy and dont phone you back. I took my car in for diagnostics test, they then sent me an estimate of an issue which we booked to fix. Then on the day they fixed it, another issue must be fixed but this was supposed to be picked up on the first diagnostics test. I really dont understand this. R15000 for 2 sensors. They quoted R7200 for the boost sensor and then all of a sudden another sensor is faulty once they have replaced it. How is this possible