Poor Service

The service that I received, from MTN has been shocking! I took my iPhone in for repairs on the 22nd Feb. I was notified that the repairs would take up to 21 working days. I then started calling last wednesday as the silence from MTN was deafening, when I was told that a technician still has not looked at the phone, I called back Friday and got the same response. This morning I called again and got the same response, which then led to me escalating the matter. I then was told that the phone still had find my iPhone on, within minutes I confirmed that it is switched off with a screenshot of proof, I was then told the phone was sent back to the store as the technicians could not work on the phone. SOOOOOO my issue is this... How was I told on 3 occasions that the technicians had not looked at the phone yet and then in 1 day the phone gets assessed and sent back to the store. Could MTN not call me to ask to turn this off? Do they not care about getting my phone back to me FIXED as soon as possible? How did all of this happen in minutes, but it took them 3 weeks to just look at the phone? If I send the hone back again, will I encounter the same horrifying experience? TOTALLY DISGUSTED!