Thank you all for the responses and offering your time, I completely wiped the nodebb db in MongoDB and re-restored it and everything is functioning perfectly again. ☺
Disable New Sign Ups?
Is there a setting or work-around to disable new sign ups?
You can disable local registration in the ACP. Relevant thread here: https://community.nodebb.org/topic/11810/how-do-you-disable-default-login-registration-and-enable-on-login-registration-through-sso-plugin