Upgrading from 16.2 to 16.3

I'm trying to migrate from 16.2 to 16.3 and every time i start up jboss it has a fatal error and the caused by is as follows:
FATAL com.appiancorp.common.web.StartupHaltingServletContextListener - Halting JVM startup: An unexpected error occurred while trying to initialize and validate the Appian data source.
Caused by: java.lang.IllegalStateException: [java:/jdbc/AppianPrimaryDS] Could not synchronize the search index with the database data.

Any Idea on what could be causing this error?

Thank you

OriginalPostID-243459