Very Dissapointed. (Sim Card Has been disconnected

My sim card has been disconnected since about 5 pm of the afternoon of 08/12/2015. I've never removed the sim card from my phone since i've done my upgrade in APRIL 2015. I cannot make or receive any calls as it shows no network. I called customer care this morning at 06:57 where they told my that the problem is my sim card and that it might be damaged. my question is how can it be damaged and just loose signal out of nowhere. I went to the Cell C store in SANDTON wanted to get a non rica'd starter pack and the guy told me they dont Sell i must pay them R140 to get a sim swap on my contract. I am very unhappy for the service delivery, I was expecting some urgent calls, but now my SIM is dead with no connection whatsoever. Are you disconnecting numbers on purpose just so that I must pay everytime do a sim swap?