Almost 2 weeks to replace a battery?

I'm disgusted by the service from the Samsung Service Center! I took my phone in on Fri 24 July because it was restarting whenever the battery reached 20% or lower. I thought the cause for this was because I had dropped the phone into water a few months prior, however everything was working fine except for this restarting issue. They booked it in (the consultant noted that my battery was a bit swollen), and I didn't hear a thing from them until I called them on Wed 29th and was told that it had been ready. I went to collect it but when I got home, it was doing the same thing. I took it back and the consultant at the desk said that my battery was swollen and I would need another one. She asked for the proof of purchase which I had thrown away. I went to get another one and they again booked it in. Despite trying to tell them that I needed it back the same day, I got no call back. I called on Mon 3rd and couldn't get a status as to how far it was. I drove there and insisted that I get it back. They then told me that the battery was only covered for the 1st year only so I had to pay for a new battery! I could have been told this a week ago! I'm really unhappy with the service!