Chosen Solution
I bought my phone a few months back and it was a refurb. I have attached an image of where the screen seems to be damaged. I coloured in the whole screen so you can see where the colour is missing, that’s obviously the damaged area. Any ideas what this could be?
Your screen is probably defective. Refurbished phones that come with new parts are almost always using the lowest quality possible. Therefore a defect is not surprising. Hopefully you can get help from the seller otherwise it will need to be replaced.
