Phone screen repairs unresolved for almost 2 months now phone lost by

On 22 August 2017 I left my Huawei P9 phone with at Cell C shop in Chatsworth (Durban), the phone is new and only had cracked screen. The purchase deal had provision to fix screen for free within one year of purchase. The consultant said it will take 21 days. Besides not getting any update on the status of my phone from Cell C I have had to continously call to find out when will I will get my phone back and told different reasons why it has not returned. The latest was on Thursday 12 October when I was told they have lost my phone and they will issue me with a swap phone. It was not explained to me what is the 'swap phone' and when will exactly my query be resolved. Today on Tuesday 17 October I phoned agained and asked about swap phone, to my surprise I was told that swap phone is a phone that had been sent for repairs. I findustry this unique acceptable that my phone had no technical fault (only cracked screen) not I may end up with a technically disfunctional phone. If that swap phone had an owner why that owner never took that phone back? I am truly unhappy with the time it has taken, the manner they want to resolve my problem. I am hoping that this action will make them expedite resolving my problem, and either return my phone or my money so I can move on.