System migration = unable to upgrade

My old cell phone fell & is beyond repair. I am due for an upgrade, MTN Direct, the MTN stores & MTN retentions doesn't have stock of the phone I want. I then contacted the iStore last week & they do have stock & could process the upgrade on Friday. I was then advised iStore can't assist due to my account still reflecting on MTN's old system & they work on their new system. No one at MTN can give me any time frame as to when my account will be migrated/log a query to have it migrated in order for me to get the phone. I can't even process the upgrade through MTN & just collect the device from iStore. Just apologies which doesn't really solve my problem. To put the cherry on the cake, I was involved in a **** today just because I commented on a MTN Facebook post regarding my unresolved query.