Tax

I am a government employee i am being taxed more than R2000 a month and now sars is deducting ANOTHER R2700 on my pay claiming i did not submitt a medical certificate and now have to pay R16000,tha i dont even know,how am i suppose to pay schoolfees and other bills.i think there is ***** going on here,i know nothing about the money that they say i owe,they cant even explain it over the foun,i think i will go to their offices and cause a scene until they reverse this money.this is abuse.it was better if i was paying for a house.our goverment is not doing things write,now its been 3 months and not being able to pay schoolfees now my child is being placed outside school premises because of the government i am working hard for.i wanna know who authorised that they deduct my money without my knowledge.can i sue sars