DSTV robbing me

I have a DSTV subscription for DSTV Extra. My payment date is 26th of every month. In December, I did not make a payment because I was out of town. Upon returning, my DSTV was disconnected as expected. Today, 26 January 2015, I am checking my balance so that I can pay. I expect my balance to be R425 + R20 + R50 +R495. But I find that I have to pay R686.83. After calling, they told me that they charged me up until 9 January 2016 therefore I have to pay those days. But I want to know WHO SAID THEY MUST KEEP IT CONNECTED? I always go out of town in December but this has never happened. Now they say they assumed that I was still around since I did not tell them that I left town. Why is that my problem???