Mtn-unisa sim swap.

Iam a student at unisa....now since this Mtnunisa data started i registered using my numbers instead of the new numbers.now my problem is that my phone was ****** meaning i lost the sim,i called Mtn and they told me that my Sim falls under unisa business for sim swap i need to send an e-mail to ***...i did on monday.

now my question is how many weeks does it take for unisa to send a student the authorisation letter so that they can be helped with sim swap?

i'am not only using my sim for unisa only,my banking institutions are linked to that number,everything is with that number.since the mtnunisa started,l i decided to carry on with my number because we were not explained that unisa will overwrite us and take control of our sims..now i cannot access my personal things it as they need to send a verification to my number.

please send me the authorisation letter asap because at MTN they said they can help me only if i have the letter from unisa. ***