Angry customer

I love the service I got at pep cell and how they treat me but one thing I hate is the phone I bought it doesn't have a charging problem the problem is it switches it self off n can take two days to switch back on.the staff at pep were kind enough to book it twice but still does the same thing.so I sent an email to Vodacom repairs in Hatfield it's a week now no response they only checked if the phone charges.so this problem it happens even if the phone is full and when it switches back on its low even if you try to switch it back on it won't light up it will do it by itself after a day or two probably it's the battery or something I restarted the phone did factory settings to clean everything on the phone still does the same thing the phone is 3 months I can't keep complaining to the pep staff about one thing they help me but the Vodacom repairs whr suppose to check everything now it will b booked I think the 3 time or fourth.im feed up it's messing with my business. If u can't fix it replc it with another phone