Shocking service

I took out a contract with Telekom and they delivered the wrong size phone. After numerous attempts to get them to exchange the units, I am now being ignored. If this is what the sales service is, what is the after sales going to be like? Terrible service and highly disappointed with the way this has been handled. It was not a difficult request and after a month of trying to get a device swoped, I’m still waiting for a response. Well done Telkom