Very unprofessional

I just found that my number has been deactivated without my knowledge and allocated to someone else, the number in queation is ********** 458, o spoke to someone by the name of Phumzile Cele, who didn't know her story and seemed like she is not even understanding what she is saying at times, she told me i needed to do a sim swap and ask for the same number but she says to me its allocated elsewhere how does that work? now what i need to know from you guys because my banking, sars and all the other important institutions are connected on that number do you even think of how you risking our information when you allocated the number without a warning? Now i need this resolved or i will be taking further steps.