OBF !!!!! DISSAPOINTMENT

<p>I purchased a samsung Galaxy J5 on saturday from a Cell c Store all was fine with phone, after going through the phone when i got home , i found whenever i went to call settings the phone says "Unfortunately the process.com.android.phone has stopped " and the network of the phone goes off and comes back ! to me this is a software problem ! i took it back to the store and they checked it and booked it in , Apparently it has reached the Service centre for assesment and it just needs a "Software update " I dont understand how a phone out of the box needs a software update , Plus why didnt a message come up on the Phone for an update ? Apparently the phone is coming back on monday , and should it still have any problems it will be escalated and il have to wait !!! Really ? More days to wait and be without a phone? its within the 7day period why cant i just be replaced with another phone ? am i not able to cancel my contract in the 7days? this Phone is a OBF ! I am not willing to sit with more problems with this phone once it comes back , also i am not willing to pay Pro rata for the period that i do not have the phone That is just Unfair !!! and **************** ! i have 2 exisiting contracts with you guys , after my back and forth experience i will not be renewing any contracts with you , i would rather go to another service provider who will not give me the run around and will supply better customer service , Please get someone who knows whats going on to help me ! im tired of going from person to person , the store only says the phone is coming must wait , Call centre cant help to cancel ! i dont mind even being replaced with the same model phone , as i do not want to sit with problems with the current a defect phone!!!!!!!! PLEASE URGENTLY HELP ME</p>