HTC — faulty mobile phone

So i bought a htc u11 for rs 48000 because previously i had good experience with htc one. But this new htc u11 had camera hardware failure within two months (Under warranty). I submitted the phone to authorized service centre at vashi and they saud part will arrive in 2 weeks time and they will repair and give my mobile phone. The phone was submitted on 18th december. Its been almost a month now and still the part has not arrived. When i call up the service centre they say speak to customer care about it. When i spoke to customer care they said, they do not have any idea about availability of parts. I have asked them to escalate this issue and some person who calls up every 48 hours to inform me my issue would be resolved soon. But when i ask them to tell me when my part is going to come they have no idea. I asked them to replace my phone but they still do not want to do it. Do they think i will wait for one full year for a part to be made available. If you cannot repair the phone then replace it, its under warranty phone.
Ticket no: [protected]
Jobsheet no: wd[protected]
Phone submitted on 18th december