Problem switching from M2 SATA to M2 NVMe Dell 5400

I have a Dell 5400 running Win 11 with factory installed 256GB M2 SATA drive which I'm trying to switch to 1TB M2 NVMe (brand new). According to manual and BIOS settings this is supported. Here are the steps I followed:

1. Created image of existing drive on external USB drive.

2. Created bootable USB thumbdrive with imaging software.

3. Powered down.

4. Swapped M2 drives.

5. Booted to USB thumbdrive and imaging software.

6. Restored image from external drive.

7. Powered down.

When I power up, I see BIOS messages looking for media, which it finds, then get the Dell logo following by activity icon spinning and spinning but not booting into Windows.

Am I missing something?