OnePlus India — one plus 6 - service not provided for device under warranty charged for diagnosing and servicing

Address:

59,1st floor,80 feet road, Koromangala 4th block, Bangalore - 560034, Bangalore, Karnataka, 560100

I had a visit today ( 01/03/2019 ) to One plus exclusive Service center located in Koromangala, Bangalore. My device is having flickering issue. There is no physical damage done to the device and the same photos are been taken by one plus customer care executive. The device is under warranty and all invoice, receipt was provided to customer care center. However, they denied to cover the device under warranty by saying the device is unauthorizedly repaired from outside. Why would a person repair a device from outside which is already under warranty. Also, they charged the amount for diagnosing and servicing for a device which is under warranty. This is really not acceptable where they just give an excuse saying some or the other reason which is nowhere correct. There are no physical damages.
Requesting to please have this case taken forward and action to be taken on not providing service and also charging for diagnosing for warranty coverage device. All invoices and job sheet along with warranty receipt are attached.

Thanks,
Hemal Gohil