Extremely poor customer service

We have been with Zen for over a year now and I always thought they were quite good. Last week, I was proved wrong. Our internet went down due to problems at Zen. It lost us income and caused great stress to the entire team as we are web based. I had to pay an IT engineer to come out immediately who charged on a Friday afternoon. When I phoned Zen, they explained they had problems that day but did not warn us in advance.
I became very angry as they were unwilling to offer any decent goodwill gestures. Another company that is greedy and arrogant-when will they learn-perhaps when their clients leave them.
Their only solution was to upgrade to a higher level service and pay more money. This is unethical and greedy. I accept problems happen but it is always to do with how you deal with them. Avoid Zen, they simply do not care about their customers as we are just a number. Having said that, without us, they wouldn't have a company.