Charging port not under warranty

I have a Samsung phone, on contract, with Mtn. The phone is about 8 months old and suddenly it didn’t want to charge. I took the phone to Samsung/Smartcare in Nandi drive to repair the phone as the phone is still under warranty. Now I got a call to say that its negligence from my side and they gave me a quote for R2500 to fix the charging port. How can it be negligence? It’s not my fault that the phone didn’t want to charge anymore. I can understand if the phone was cracked or fell in the water. I have been a great fan with Samsung , but NO THANK YOU…..i will never buy a Samsung again as they think they are very clever…they tell you that you have a warranty when you sign up for a contract , but when you want to claim they tell you a different story….R2500???? I can flippen buy a new phone.....