Product found defective -No replacement/ refund as per customer demand

I placed an order on Flipkart for Motorola e4 Plus mobile handset and was delivered to me on 29.07.2017. It has no screen protection, so I bought a tempered glass for it’s screen protection the next day but within a days I saw the handset is not working while on charging but comes back to normal after disconnecting the charger. I did all troubleshooting with expert’s help and also from flipkart but all in vain and so I raised an replacement order with flipkart as they allow replacement of products within 10 days from delivery. I raised replacement on 01.08.2017 (attached documents). They made a technician visit to slove the issue. The technician came the next day, 02.08.2017 and said that I cannot use the handset with tempered glass for screen protection, which is the reason it is not working.I never heard in my life that this is technically possible. It took 10 days for them to give this report to flipkart when my 10 days replacement ended. Please help me. They are not co-operating.