Waiting 3 months for my phone

<p>I bought a new phone and it had network problem, i return to the store (19 April 2016) and they told me i should come back after two weeks max. Today is 15 June 2016 ive not get it, if i go there they tell me I should come back the following week. Ive been there 8 times now, please help where should i complain.</p>