No boot loader after Carbon Copy Cloner

[Jammyjam1982]

Hi!

I have installed Sierra on a new SSD through CCC.I also cloned the EFI through Clover Cloner. Everything looks the same on both the SSD's
Now booting only works with the old SSD with the original Sierra beside it. It is like it lifts on the old SSD's boot loader.
When I remove the old SSD and I boot to the new SSD I get the Error of selecting a proper boot device. I can't even enter the Bios.
I really need a solution, because I want to erase the old SSD to install Catalina on.

Specs:
i7 2600 Sandy Bridge 3.40
Asrock rx570 8 GB Videocard
16 GB DDR3 Ram
P8H67Mpro Motherboard with UEFI version 3806

 

[Going Bald]

What happens if you mount the old drive EFI partition, copy the EFI>EFI folder to desktop on the old drive, unmount the old drive EFI, mount the new drive EFI partition, copy the EFI folder from the desktop to the new drive EFI partition, shutdown, disconnect old drive and boot?

If this does not work, use the old drive to boot the new drive, then run the latest Clover installer pointed at the new drive and see if it will now boot itself.