Grey Line on the Mac Air Screen

That does not look good at all. You can try the following troubleshooting tasks and see whether that resolves the issue. I strongly feel that this one is a hardware issue.

1. Reset SMC by following the directions applicable to your MacBook here ➔ How to Reset SMC. If that does not solve things then-
2. Reset NVRAM/PRAM by following the directions applicable to your MacBook here ➔ How to Reset NVRAM/PRAM. If that does not solve things then-
3. Enter ➔ Safe Mode and see if the screen issue still exists in Safe mode. Log out of Safe Mode and then reboot computer. If that does not solve things then-
4. This is probably a hardware issue and related to the Display or the connecting Cable or the Logic Board. I recommend that you have your MacBook Air examined at the Apple Store or at an Authorized Service Center.

Axel F.

Hi, have you solve it? Mine still not working after trying the solution mentioned above. If you have solve the problem can you please teach me? Thank you very much🙏🏻

Good decision. You are welcome.

Axel F.