Question NVMe drive not recognized in top slot on B550M Aorus Elite (rev 1.3)

[JustRelaxASC]

As the title says, my Kingston A2000 SSD is not recognized in the top slot, but seems to be working in the bottom one. Drive is healthy and working in another build.
Sometimes the system boots and recognizes that NVMe for a while, say 10 to 30 minutes, and then suddenly it disappears and isn't recognizable at all in BIOS either. I have no idea what could be the issue besides a malfunctioning motherboard (it's brand new).

I have the OS on another SATA drive and other 2 hard disks as well plugged in, I tried unplugging them and changing their sata slots, but NVMe isn't recognized either way.

 

[Lutfij]

https://www.gigabyte.com/Motherboard/B550M-AORUS-ELITE-rev-13/support#support-dl-bios
What BIOS version are you on for your motherboard?

On second thoughts, when posting a thread of troubleshooting nature, it's customary to include your full system's specs. Please list the specs to your build like so:
CPU:
CPU cooler:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:
OS:
Monitor:
include the age of the PSU apart from it's make and model. BIOS version for your motherboard at this moment of time.

I have no idea what could be the issue besides a malfunctioning motherboard (it's brand new)
If the afflicted drive works on another known working motherboard, then it's possible that the motherboard is at fault. If the drive exhibits the same issue as your current platform, then the faulty could be your drive, not the motherboard.