Accomplice to ******** activities

My contract phone was ****** on the 13th of October 2022. I called MTN to have the cellphone and simcard blocked. I recently got a new phone from the insurer and done a simswap on the 19th of November 2022. I then received smses on my phone stating that I have a Momo account and should rate the lady who assisted me. I checked the Momo and found that this person has taken a R10 000 loan and has used over R3000 of it. I called and asked who would be billed for these transactions but have failed to get proper answers. I want clarity as to why the simcard was still active after I reported it ****** also I was billed an extra R1000 on my account this month I would like that to be refunded immediately as I didnt have the phone or sim with me after the 13th of October 2022. I believe proper credit checks and KYC wasnt done when the Momo account was opened for these theives and I fear that even my personal information wasnt protected by MTN as they should've. I would appreciate a response from MTN and if I dont receive one within 24 hours I will escalate this matter on Twitter!