Billing Can't contact call centre

I have loaded 60rand airtime using the points I have saved... Yet when I try and make a call I am told I have insufficient airtime. To make matters worse I try and contact the call centre as I was previously able to do by dialling 173 only to find its not possible to speak to a consultant? Does the call centre even exist? I also have a micro sim which I would like to have the number ported to a nano sim as I have a new phone, yet when visiting the store o receive incorrect information about what is needed. I am told I need my proof of residence and ID, which I returned and brought along, only to be told I also need an affidavit after having to wait in a long que. I would not purchase airtime or data from them. They are unreliable and who knows when they will allow u to access it. Currently using Telkom mobile in my knew phone. Guess porting the mtn number to Telkom might just be easier and a better option since I have never had this issue with them.