[✗] There was an error uploading your debug log.
* Please try again or contact the Pi-hole team for assistance.
* A local copy of the debug log can be found at: /var/log/pihole_debug.log
It did not include a specific error why it failed.
You may have better luck in the issues page of the HA add-on github, as we do not directly support it.
Though, if you do get to the bottom of it there, please feel free to share the solution back to this thread in case any future uses come across the same issue
All machines including pi-hole and router are on 172.16.0.x/24.
I think I found the issue.
I'm running Parallels Desktop on my Mac with Windows as the guest system. Pi-Hole actually registers both my Mac and the Windows guest with the same Mac address. Other apps like LanScan do see the correct Mac address.
So, when I make a reservation based on Mac address the DHCP can't give both systems the same IP, there it goes wrong I presume.