Dark Area On Monitor

Hello everyone.
I got a second hand monitor earlier today, and a few seconds after turning it on it gets this dark spot:

 Just to clarify, this dark spot only appears about 20 seconds after turning on the monitor, prior to that it's just fine.

Looks like the LED strip may have a bad connection.

Any idea on how to resolve an issue like this? Thanks.

Unless you are very skilled with a soldering iron. you are probably out of luck when it comes to fixing it your self. Just RMA it if you can.