DELAY IN CONTRACT APPLICATION

My friend once took a contract phone for me under MTN in 2017, this year when she wanted to take a contract phone they asked for my Sim number in order for them to process the application, unfortunately my sim has been cut and it no longer does have the sim number and now because of this MTN has for the past two weeks said nothing to my friend regarding the application, i do not understand why my sims number is needed when my number was once in your contract and i also do not want to have to use another number from. She was once told that the application has been approved but because of the sim number she was told to re-apply and since then nothing has been said to her, its been two weeks now