To me that sounds exactly like what happened with my first SSD before it failed completely. It would randomly disappear then one day it did and could never be seen again on any PC. So I would definitely attempt to RMA it as defective.I had random drive disappears (where the power had to be cycled to recognize the drive) with the G1 512GB WDC Black nvme drive on ryzen. Replacing the drive with a Samsung 960 fixed the issue. Haven't tested it on an Intel system yet.