terrible service

My phone was ****** this past weekend along with my ID. I tried going to a cell c store for a sim swop but because they require an ID document, I was advised to do contact the call centre. I contacted the call centre and the consultant asked for security questions of the last numbers I contacted and data bundle or airtime I entered. I do not use my phone data to roam the internet and I do not use my phone to make calls so I gave the information I last remembered which was from a couple of months ago. The consultant on the phone advised me after my 3rd attempt the information was incorrect. My banking app along with all my contacts and information is stored on this number and because I don't remember information from 10 months ago, my card is not blocked and I can't do a sim swop. I am now at risk that the ******s might be able to enter my phone and retrieve all my information and money in my account because cell c does not ask you personal information relating to you that only you should know but information on your phone that you will never remember. very frustrating and I'll be moving to a new service provider from now on!