Brand new phone never worked

Went over from virgin mobile to cel c got a nokia lumia 630 on contracr 20 dec 2014 21 december phone crashed. Took it in they hard rebooted it three weeks later took it back would not read my sd card and could not conect to computer driveware not instaled took it to their technical department they sent me to nokia direct instead of taking my phone to nokia themselves. Two weeks got my phone back end feb. Still not working properly. Took it back again. Two days got my phone back it is stil not working. Now my whatsap immages wont save to my phone and still cant conect to computer. Nokia technitian said dud phine