I just download this last NCP img, however, it fails to boot.
the screen shot is a attached here.
I have run NextCloudPi_RPi_11-27-20 until the day before yesterday. NC failed after an unexpected electric stop. So I went to get a recent version.
Latest image works on and is build for arm v72 and v8 (64bits) and higher.
v71 and below (32bits) are no longer supported, we simple have no manpower for backward compatibility. 
Check yours by running
sudo uname -a