Monitor display issue

Hi Team,

I had purchased dell monitor keyboard and a mouse last year on 12 March 2020.

From yesterday 11 March 2021 the display on the monitor is giving issues and the top left corner till the middle of the screen shows blurred and distorted lines. 
I had called the customer support and they said the 1 year warranty has expired. But I had ordered this monitor from Amazon on 12 March 2020 and have received the delivery 4 days after.

I think I should still be within the warranty and have requested the customer support for a replacement of monitor but not getting much help. Any leads would be helpful. Do I need to escalate it further.

thanks devendra