S5 VODACOM PHONE

I am struggling to get somebody to replace my S5, this is an ongoing struggle for months now, my phone looses its network, then nothing is coming through, then I have to restart the phone some days 6 times a day, I have been to all the vodacom shops around me, everybody has there own opinion, and nothing works, eventually somebody told me to take mt phone to Samsung in Menlyn its still a new phone they must replace it, the lady there told me my phone and sim doesn't talk to each other, (after a year????), so I went to the vodacom shop they changed the sim, but couldn't get the network back, so they took the phone for repair,(they didn't have a loan phone for me) after a week a phoned and they said my phone is back but they didn't do anything to it, but now they will order a new motherboard, I received my phone download everything and the same happens again, I phone them then Riaan told me I have to give the phone in again, after a screaming match with him, he said I had a bad experience with other Vodacom people, he will help me, and he have a loan phone for me, when I arrived there the loan phone wasnt working,I received my phone but is still doing the same, looooosing the network