ITC SERIAL NUMBER MESS UP

I have blacklisted my phone and got the ITC ref number for msisdn correct but the imei number of the ITC ref differ with the last digit. On the phones box it ends with 6 and on the sms it ends with a 2. My insurance does not approve this last digit that differ and after many phone calls vodacom states it is just like that and they cant change it. How can i resolve this issue