Hi Welcome to JustAnswer.
Please give me screenshot of it . It will help me in identifing issue.
It seems the problem is because of struct pixel in your screen. Please try LCD repair tool.It will fix the struct pixel issue in your screen.Below is the instruction to use it :-
1). Select 1 of 5 basic color to test your screen, looking for stuck pixel. 2). Click on Fix my screen, the graphic will try to massage the stuck pixel back alive again by getting it to change rapidly.
Please copy and paste below url to your browser.
If you want I can also take control of your PC and resolve it for you.
Let me know if this helps. Please provide your valuable rating to me.If you are still facing issue. Let me know, I will take cotrol of your PC and try to resolve it using screen sharing option.