In this case, you will have to reset root password then take a ssh access to VCSA and reset sso admin password.
If vCSA 6.0:
Reset root: https://www.unixarena.com/2016/04/reset-grub-root-password-vcsa-6-0.html/
Reset sso acc: VMware Knowledge Base
If 6.5:
Reset root: VMware Knowledge Base
Reset sso acc: VMware Knowledge Base
If 5.5:
