Telkom Staff need more training so we don't have to pay for their mistakes

Last month i had to call telkom to ask why they are still billing me for an address i haven't lived at in 7 months. The sales consultant managed to get to the bottom of it after half an hour of my airtime draining out. The person who was supposed to cancel my contract never did their job correctly. Today i am once again receiving a bill for this non-existing account at the residency where i do not even live. And to be honest, i don't have the airtime or patients to call these people everytime one of their ill equipped people doesn't do their jobs properly.