Damaged phone disappears into abyss

My Iphone6 which is insured with MTN insure was reported in November last year. The phone was finally collected in January 2016 (!) and despite the SP's promise of a loan phone, there were no handsets available. Since then, I have had no feedback and cannot get through to the call centre (on line for 45 minutes without any answer), I get no response to my emails and going to the local store is also of no help as they cannot do anything other than also send an email. It is frustrating as hell as I use my phone for business - and now it seems to have DISAPPEARED!! I am highly dissatisfied because I PAY for this service which seemingly doesn't exist. Grrrrr .... Not sure how much longer my 15plus years with MTN will continue if this is what I can expect