In the admin-agent log, you see message similar to:
"msg="failed to update system admin password for registry harbor-1459587925: 400 Bad Request:{\"code\":400,\"message\":\"the password or secret must longer than 8 chars with at least 1 uppercase letter, 1 lowercase letter and 1 number\"}\n""
Note: The preceding log excerpts are only examples. Date, time, and environmental variables may vary depending on your environment.