Laptop pixel error what to do?

I bought a laptop a year ago and there was such a black pixel on the screen. I ignored that, and over time it has become bigger and bigger. Today a square of turquoise pixels has been added. What can I do against it? Can one solve this alone or does one need a specialist for it?

Here are some pictures:

The display seems to be defective. It must be bought a new one and be changed by a professional, if you do not want to have it.

Do you still have warranty? If so, just change, but alone can't do anything!

Hi

Look here what would cost a new installation: https://www.ipc-computer.de/

Unfortunately, this is from eBay, so I did not buy in a shop, but on EBay wars new and it was also in packaging