Computer broke after auto-update to latest beta

My computer tried and failed auto-updating to the latest beta.


In the middle of the download, the progress bar froze. Then an error came up "There is not enough free space on Macintosh HD - Data to install. Quit the installer to restart your computer and try again." It offered options to boot from, and I selected the one option Macintosh HD 10.15.1. Now, when I power on my computer, it prompts for password, tries to load, and then powers off.


Is there any way to fix this without wiping the computer? Thanks!