Can't get a sim swap right

We have an existing contract with mtn with a phone that uses a normal sim. We got a new phone that needs a micro sim and therefore paid for a sim swap. It's supposed to be activated within 2-24 hours. Its now been more than a week and we still can't use our phone as the sim swap has not worked. Been into the brach twice since and phoned 808 to try get some progress. Person at the branch tried another sim card and its still not worked. Does mtn not know how to control their own network?