Screen vertical lines after upgrading SSD

Hi there

I’ve got a Macbook Air 2017 13” A1466 and I decided to upgrade the SSD from the stock 128 GB to a Samsung Evo 970 Plus 500 GB - with adapter.

I unscrewed all the pentalobe screws, all came out just fine, except one on the side - but the last one came out eventually.

I disconnected the battery cable, replaced the SSD with the new one with an adapter, reconnected the battery, put the cover up and seal it with the screws.

To my surprise, when I powered on the machine - the screen showed vertical lines, and it still does.

1st I thought it’s got something to do with the SSD, so I replaced the new SSD with the old one. The screen remained the same with vertical lines.

I tried plugging out and checking the display cable, but everything seems OK there.

After that, I used a Thuderbolt 2 to HDMI adapter and connected the laptop to my TV.

Here, it works perfect, as shown.

I’ve also reseted the NVRAM using the key combination Command+Option+P+R.

Any suggestion is helpful, since I don’t think I could have possibly damaged any hardware - because I was very careful.

Thank you !