Why am I getting blurred lines on screen?

Hello,

I have just replaced the screen on an HTC One M7. Repair went well. However once booted. on certain windows (not always but usually) lines of text will be blurry (not all text on the screen, only some). If I swipe the screen up and down the blur follows the text. Not sure what this is. Any ideas?

I have cleaned the contacts of the lcd with .99% in some hope that they were only dirty. thank you