Bad after sales and worse service quality.

We have 2 Suntank Geysers, a 300L and a 200L which were both serviced about a month ago, we are by the way paying for these services, a week after we realized that the 300L does not heat up, we phoned and reported it and about 2 days later they came out to find that there were a glycol leak and repaired it after they were here to service it just over a week before. A week later we realized that the other geyser does not heat up properly, I phoned to report it and now there are no answer. I know that any company is as good as the people doing the physical work. You should get a grip on the people working for you or a grip on yourself.