A SIM Swop can't be done -No.has disappeared ****!

My Mom has a contract that expired July 1st. She would like to keep the number and called Cell C, queried if it's possible? Call Centre said unfortunately because the contract SIM is a data SIM it can't be done BUT what can be done is to buy a new SIM card and from July 2nd onwards get that new SIM rica'd and call into the Call Centre and they can do something called a \Number Conversion"aka \""SIM Swop\"". Bought SIM on July 2nd went to get it rica'd at a Cell C branch on July 4th and now the number doesn't exist anymore...? ****! It's done a HOUDINI! They cannot find that number linked my Mom's ID number. I then called into the Call Centre and was told the same thing"