Sim swap battle after migrating from contract

I've been an MTN loyal customer for 11 years. I lost my phone on the 18/09/2015. The very same day I called MTN to migrate the 2 numbers to prepaid. My contract has ended and didn't want to renew. <br> I waited for this to go through so that I can do the sim swap for my other number when it is prepaid. This was still not done around the 25th and I advised them that I will not be liable for airtime loaded on my phone on the 1st as I cancelled this long time ago. <br> A debit order of R531.50 went off my bank account on the 01/10. I don't know why this happened but anyway I called 3 days back and I was advise that my other no has still not been migrated as I still owe about R200 and I must sort that out with Retentions. <br> I sent an email to retentions querying the migration of the 071 number and to date I have had no response. I also tried to call no answer.<br> Now I'm struggling to do a simple sim swap for my 073 which was migrated on the 06/10. I've bought 2 sim cards and once I try 2 do sim swap I can no longer dial 173 it says call barred. I really don't understand this so I called from another phone n was told 2 keep on trying.It has been 3 days since and I really need this number.