How was the incorrect number issued?

I had tried calling my wife on Saturday only to realize that a guy had answered on her number. When I spoke to the guy he had told me that the number was issued to him (Sim Swap). Basically my wife has had that number for years and is still using it, In addition to that the sim card was Rica. So please explain to me what process was followed when the number was issued and was all the relevant information there when this guy did a sim swap so that they could have cross referenced it to the original application. My wife had to call in and log a call ( Sunny boy- Ref ***) and is now left without her number in use of which she uses it for her work(Payroll) also she does banking on her phone so what if information was sent to that number and things were changed who will now be ACCOUNTABLE? This is extremely serious and I am very upset and disappointed but I promise to take action should this not be dealt with and if any losses are incurred.<br> 48hrs have passed already, DOES CELL WANT ANOTHER BANNER or should I just escalate this to Jose Dos Santos or Zeona Motshabi...You be the judge.