Help needed regarding Asus Phone issue

I am owner of Asus Zenfone Max Pro M1 6GB RAM variant, which is still in warranty.
For past few weeks, I was not satisfied with captured images. Finally, I dug deep in camera settings & found that max picture size I can set is 5MP. I also looked at properties of captured images & found that images captured 2 weeks prior have 15.9MP size & recent images have 5MP size. Then I formatted phone hoping it to be software problem, but problem persisted.
Then I installed DevCheck app and found that the app doesn’t detect primary rear camera. It only detects secondary 5MP camera. Hence Camera is capturing images in 5MP size.
Then I submitted my phone to Asus service centre on 7 June 2019. Till today, I my phone has not been repaired. I was given 10, 13, 17, 20, 23 and 25 June as fulfilment dates & I was told to wait indefinitely as company is not sending camera module despite repeated requests from service centre. Service centre people are saying that they are helpless as camera module is not available with Asus India.
I have also lodged complaint with Customer Care, but there is no respite. Service centre has also steadfastly refused to provide a standby phone till repair has been carried out. Today I requested CC to escalate the issue. I was told to expect a return phone call via Senior CC Team, but I have nt yet received a phone call.
This reply is worrying for a phone that was launched barely a year ago and has deeply diminished my confidence in Asus. I was very happy with my phone’s near stock UI and great performance and was looking forward to purchase newly launched Asus Zenfone 6, but now I have postponed my purchase for a better alternative.
I request knowledgable friends on this forum to provide me links of social media or emails of cocerned authorities of Asus India, so that I can find swift resolution of this problem.