cellphone problems

I bought a Blackberry z10 @ exact in July 2014..early this year it started To give me problem by just don't want To switch on so then i rook it back To exact on 3rd of match the store manager told me it Will go To repairs and that they Will call me but they never die so i was the One who always went there and i found out that the My cellphone tot delivered To mobicell instead of Blackberry now mobicell wants a release amount of 400 so they argue about who should pay that amount.its been nine months now the manager always tells me One thing over and over until now...please bare with me if ma cellphone cant be released i need a New One because One year warranty passed and it was already with them...i need a New cellphone i already lost many things i cant lose soms more..please help me