Bosch appliances don't work

We are not impressed with Bosch (their appliances or their service). We bought a Bosch dishwasher in December. Just a few months later, the dishwasher stopped working. We called Bosch and they sent a guy a few weeks later to fix the dishwasher, or so we thought.

We only use it once a week, so when we wanted to use it again, we realised that it still wasn't working. Every time we call them again to let them know, they say they would call us within a few hours. We are still waiting for their calls. What does it take to get our machine either fixed or returned so that we can get a dishwasher that actually works?