samsung galaxy s6 edge

i took out a brand new contract with vodacom in july two weeks after having my phone it just switched off i took the phone to vodacom they told me there is liquid damage on motherboard but the phone never fell in water or anything than when i got my phone back i switched it on it when on did downloads everything but than the phone didnt want to charge so if its water on the motherboard the phone wouldnt have even went on than they sent me a quote of 8500 that i should fix a brand new phone that i just took out now i am sitting with a phone that does not want to charge for 4 months