Double purple image after backlight repair (SAMSUNG UE55KU6472)

Hi, I recently tried to fix this 55” Samsung tv, on which i could see image using flashlight only. I used backlight from UE55HU64** tv with the same ( looking ) LED backlight. After installation the tv went into bootloop without any sound or logo for Split second displayed. Only backlight went on bright/off/dim and tv restarted after this.

I tried using the tape to block some signal to the right side of display. This led to tv to boot but with some defects on image (vertical line right in the middle of the screen) . So i removed the tape, where to my surprise tv booted but image looks like this.

Any idea what mať be causing the problem here?

Thanks