"Failed to start Login Service" error after reboot

This could be caused by a few different things, and will probably require some output analysis from a few different commands to figure out what's causing the issue.

I would look into this systemctl guide for some more information that and may be useful in figuring out the "Failed login service" error you were getting.

Another useful tool is journalctl. I would give this page a look over which covers how to use it. One specifically useful piece of info from here is the "-u" flag (i.e. Passing the name of a systemd unit with the -u option shows logs for that service).

Hope this helps!