Cell c device insurance makes their own time i have 11 emails to proof this

Cell c device insurance incorrectly billed me for more than six months even though i did cancell my insurance with them in may , it has been three weeks now and they still havent refunded me i have a few emails stating ot should have taken 5 to 7 working days then i will have received my refund but it has been more than that and now they want to tell me it has been handed to the finance department it will take an addisional 7 to 14 working days now for something that was not my fault but they collected the money from my normal cellc ****rack account now i have to wait for them dont trust them at all