The fact that a SATA M.2 SSD was originally installed was a hint. The 9343 is an older system (around 8 years roughly) and only supports SATA M.2 SSD. A search at Crucial shows no compatible M.2 NVMe SSD.
I have tried to install a new NVMe  SSD in the XPS 13 9343 laptop. When install windows its detect but complete first phase of installation after restarting its unable to boot & show unable to find bootable device. I have tried 2-3 times but its give same error. earlier this laptop used SSD SATA 256GB. Can you tell me why we are facing this issue? Is this unable to support NVMe SSD?  
XPS 13 9343, NVMe SSD, cannot find bootable device