I bought an iphone advertised as new, its used, they wont respond or respect my warranty

[fran_schof]

I bought an iphone off a large seller REMOVED about 4 months ago. It was advertised as brand new bla bla, with 12 months warranty. i have had massive problems with it, and recently took it into a store to be looked at as the seller would not respond to me. i was told my iphone is not new, has heaps of dodgy parts, has had its screen replaced before etc. The phones battery home button and power button stopped working due to the shody repairs they did. i have essaged them but they wont respond. is there anything i can do???