Migration error

We’re evaluating auth0 for our company, and I’m testing out this plugin for our WordPress site. I set it up and connected it to our auth0 account.

For the first few users that login, everything works fine and the users are migrated over. However, after the first 3 – 4 logins, we start getting an authentication error whenever someone else tries to login and this appears in the error logs:

migration_ws_login 0 Signature verification failed

however, their username and password is incorrect and they can still login through the regular WordPress login.

Any idea what could cause this? I tried uninstalling, re-installing, checking the auth0 community forums, etc, but no one else seems to have this issue.