cell c terrible service and lies

i upgraded my cell phone contract with cell c to a Huawei P9 lite. in July i called the repair center because my phone was not coming on. It used to start up and switch for few minutes and then comes some recovery mode thing. my screen did have a crack months before but the device worked perfectly. My cell phone is lying in the repair center from the 24th july and not yet repaired. they say the warranty fell off because of the crack( which was not told to me when the terms and conditions were read) they said they were going to listen to call recording and get back to me but nobody ever calls. i have made several calls even spoke to the supervisor which he assured me he was going to get back to me. he keeps making an excuse that Huawei is rejecting the repair and he will send them an email. this is not the first time we having an issue with cell c repairs previously i had sent my blackbeery z10 and had the same response.