How can i be owing SARS??

Good day,<br> <br> I have called the SARS offices today (19/02/2015) to know about the message I have received stating I owe them R789. I was told that this amount is for 2013 SARS returns. Please advise as to how come am I owing because I did my return around March/April 2014 and was returned -R1300 into my account as it states SARS was owing me. Please clarify as to why since I have done my reurtn again in September/October 2014 I was only notified that I'm owing SARS?? I really don't understand as to why am I owing 2013 as to when I did the return I was refunded the -R1300? I dont get it as to why am I owing for 2013 for the return or refund was for 2014.<br> <br> Not pleased SARS payer...