Bad service from the manager at the cellular store

I bought a Samsung S5 black from Autopage Nicolway January 2015 only to learn that this was not a new phone but used as it was blacklisted due to non-payments, I took up with the store manager and they swapped me with another Samsung S5 white, firstly they sold to me a used, my phone is now damaged and samsung is not fixing it as the proof of purchase states black, I spoke to Tanya to see if she can empathize and expedite the service but she gives me bad attitude. I told her I have been calling Autopage nicolway from Thursday with no luck, but she didn't seem interested to understand my frustration, to top it all apparently all her seniors are on leave? This is not fair as I feel i am not the only customer they sold a USED phone to