3 month old dudd phone vodacom wont replace

I got an LG G3 in January on upgrade contract, Ive had it 3 months and its been at vodacom the last month, 3 seperate bookings for repair. It restarts everytime I touch the screen. 9 April they replaced screen, 18 April they supposedly upgraded the software but I got it back and it asked me for 500mb update when I switched it on. I got home and its still restarting everytime I touch it. Took it back the 27th April and they assured me a manager would call me to escalate it. Today I got sms saying its on its way to canal walk for collection. No call. The phone is 4 months old, I pay R800 a month for it I want a new one, its a dudd phone. Called canal walk tonight to speak to manager maneeb and ashley put me on hold for 10 minutes wasting my airtime, I ran out of airtime and even tho I gave my job number no one called back. I want a new phone its a dudd. Im not going to fetch this dudd phone, you are wasting my time going back to fetch this thing, its 4 months old and been for repair 3 times, im not paying this month for something I dont have. Please call me now. Thank you.