Second time already

I am absolutely furious with Sony as i laid a complaint almost a year ago about a cracked screen. I used my own money and repaired my phone about a few months ago..,however this morning, my phone laid on my lap and the next thing a line appeared across my screen as the phone was on my lap in the car with the sun on it. if that has some effect, i do not understand how i was not informed about that! i highly doubt that was the cause i think that my screen was repaired incorrectly. If that is the case i want my phone repaired free of charge as this is totally unacceptable!!! i paid a lot for this phone it is in fact more of a burden to own than anything. From the software/features and screen issues i can vouch that i will never use sony again.