GALAXY S6 5 DAYS OLD PROBLEMATIC

I have been a loyal client of Cell C for +-8 years and have just recently upgraded my contract to a Galaxy S6 handset. Firstly the unit that I received had no sticky plastic covering the phone when I received it, then after 2 days of using applications such as facebook, Instagram and whatsapp would stop working the device just telling me the application has stopped ( while I am using/ browsing). I have uninstalled and reinstalled and updated these apps numerous times with the same issue. Day 5 I battled to charge the device with the USB charger and eventually day 6 I got the unit charging. because this is a new phone I did not want anyone working on it. now that I have taken it in for replacement within the 7day period and after 7 days no contact from Cell C Tygervalley I called in just have one of the consultants inform me that there is nothing wrong with the phone Cell C will ship it back to the store within 2 -3 working days. I am not Happy with this service and feel like just cancelling my contract because I refuse to take the same handset for the next 2 years.