Hi,
Please do try these troubleshooting steps that may solve that issue.
- Start by doing a hard reset, remove the battery and AC adapter then press and hold the power button for 20 seconds. After the reboot check if you'll get the same pink line on your display.
- Try to connect an external monitor and see if the same problem will persist on it because if it does that means it's the graphics card that has the problem.
- If it's not happening on the external display that means it's a problem with the built in display only and one solution would be to check the ribbon cable that connects the display to the motherboard and if all these will not work a replacement would be needed.