Poor service with Mazda

My car is not even a year old and I have already been experiencing problems with it such as shuddering noises, etc. When I took to the Mazda Umhlanga dealership they told me that there isn't anything wrong with it. Also, just yesterday my car, which us supposedly a brand new car has battery that doesn't want to work. I used the car on Tuesday and it was fine. I made sure that when I switched the car off, that nothing was left on to save battery power. I tried to start my car since yesterday morning, only to find the battery stone dead. I called the dealership but they told me that I van only sort this out with roadside assistance. So, I tried calling the number on the warranty book several times since yesterday but nobody answers the phone, there is only a voice-mail to send messages but that to nobody responds to the messages. I even sent an email but that also falls on deaf ears.