Nokia India — irresponsible handling of item

Address:

Kottayam, Kerala, 686521

I have purchesed a nokia 7 plus on[protected]. Unfortunately i have got into an accident and the screen broke as a consequence. As the product was still on waranty, i took the phone to the nokia authorised centre at kottayam, kerala, india (Tba rd, kodimatha, kottayam, kerala 68600) and got the screen replaced paying the full amount.
Due to highly irresponsible handling of the phone, when they glued the screen back to the body, it left had a small gap between the screen panel and the body, resulting in dust entering the insides of the phone and the front cam is full of it, leaving it absolutely useless.
Then i took the phone back today, after 2 month, as tings was only getting worse. When i reached there, they said that my phone was serviced by the previous owner of this dealership and they cannot take responsibility for any error from their part. Then he directed me to another centre in kottayam (Flex mobiles, authorised nokia care, tb road kottayam), which was nearby, but received the same reply.
Both the service centres declened service to a product under warranty, for a problem that came solely because the company authorised centre had the phone handled by people who had absolutely no regard for the product or the customer.
I would like to get this issue resolved, as i am not intrested to carry a phone with a front camera, that became useless after the company authorised centre did a bad job to it.