Reliance Digital — newly bought ac (hitachi sac 1.0t) machine non-functioning. pcb is taken, but no response from reliance resq

We bought ac (Hitachi sac 1.0t 3sinv waza3200i 312eaea).ac ran hardly for a month or so. Noticed problem, called reliance resq two times. 2nd and current service request number is [protected]. Technician on his 1st visit on 28/8/2018 was not able to identify the problem. On 2nd visit, another technician took outdoor pcb and informed the pcb will be replaced by 10/9/2018. Till now, there is no update from reliance resq. Each time, we ask about update, they response they have not received part from brand.
Is there no escalation process?
If we can not run ac in warm days, why have we purchased it?
First, very poor quality of product is supplied which followed by very irresponsible service from reliance.
Sorry to say, but after tierless effort of getting a solution we, as a customer are now feeling helpless and being cheated by this big brand.