Configurator 2 disabled Boot

After connecting my M1 to an Intel Mac where I started Configurator 2 the M1 boots in a loop, seeing the Apple Logo and the progressbar until half and then restart and same again in a endless loop. When I connected the M1 to the Intel Mac with Configurator 2 open I set the M1 in DFU mode and Configurator 2 said it need to download and install something ( "1 item" ). After that it restarted and I saw the M1 in DFU mode again after Configurator 2 restarted. I didn't do any restore or revive. I closed Configurator 2 and restarted the M1. From thenon it is in a boot loop. I opened the recovery mode on the M1 and First aided the Macintosh HD drive and the DATA drive. Both successful without any errors. When I boot the M1 in option mode to see which drives available I don't see the Macintosh HD anylonger only the Options entry. How can I make the Macintosh HD be able to used as Boot drive again ?

I tried to use bless but it fails with:

bless --folder /Volumes/Macintosh\ HD/System/Library/CoreServices/ --file /Volumes/Macintosh\ HD/System/Library/CoreServices/boot.efi --setBoot <> Could not determine partition for /dev/disk4s1 <> Could not determine if partitiion needs booter <> Error while updating booter for /dev/disk4s1 <> Unknown system type

Could be fixed by reinstall macOS via recovery mode. No data loss. BUt doesnÄt explain why Configurator 2 destroyed the boot sector.

Configurator 2 disabled Boot
 
 
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