Apple India — iphone 7 no service issue and pathetic apple support

I have an iphone 7 which shows No service issue since past 2 months, model A1660 which is eligible for replacement by Apple.
I had submitted my phone to Apple service centre 05/04/2019 and they replaced the screen saying the issue would be resolved and charged 13k for the same and gave the phone back on 20/04/2019.
But the Issue Again Appeared in 2-3 days, so i submitted the phone again on 23/04/2019 .
The phone had intermittent issue, once the issue occurs if we switch off the phone for 4-5 hrs and switch it on the issue is gone.
The Service Center asked me to collect back the phone in 3-4 days saying they observed the phone, but couldnt find any issue, so i contacted Apple Support India, and on their support assistants word that i should collect and use the phone, and if issue still persists, then they will get it resolved, i collected it on 27/04/2019.
I again got the same issue after a few days, so i contatced Apple Phone Support, and told them about the past 2 expiriences, and the main issue here is every time you call Apple Support you need to talk to someone New and the person handling the issue previously cannot be reached back again, even though we have their Name and Extension Numbers nor do tthey Reply back to emails .
Also the Sevice Center Refused to take the phone again, saying there is no issue and the phone i s fine, so after 3-4 hrs of explaining the Apple Phone Support assisant, she told me that yes the phone Qualifies for a replacement, and that i should give the phone back to the same service center and she even spoke to the service center to accept the phone on 11/05/2019 .

The third time I gave the phone and showed the screen recordings from different times and they agreed that there is issue.
But again i got a call from Service Center on 21/05/2019 to collect the phone saying the couldnt Find any issue in the phone .
Inspite of knowing that the model is defective, apple is not taking any action and saying there is no issue.
When i called the Apple care exec on 22/05/2019 and asked him to escalate, he said he is the last point of contact and we can't do anything, we will have to collect back the phone .
Service center says talk to Apple they can't help.
So Should i be going through this to and fro, o[censored]sing a faulty phone, and going to the Service Center that is 1.5 hrs away from my home and if there was no issue, then why did they ask me to get the screen replaced in the first place, because my phone was already OUT of warranty, i could have bought a new phone rather then spending 13k on screen replacement .

This is the link where they state that it is a defective model
https://www.apple.com/support/iphone-7-no-service/
And NONE of the Apple guys told me that this cannot be replaced as it has been bought from US, infact they charged me for repairs
I feel Helpless, and very MENTALLY TRAUMATISED, as i can do anything about the UNJUST Treatment i am going through.