How to generate a diff from 2 databases using mvn liquibase?

Question

I have two separate databases running on port 3306;

1. jdbc:mysql://localhost:3306/a
2. jdbc:mysql://localhost:3306/b

Basically B is an updated version of A. I've been trying to generate the diff from this 2 databases using:

mvn liquibase running command:

mvn liquibase:diff 
    -Dliquibase.url=jdbc:mysql://localhost:3306/a   
    -Dliquibase.referenceurl=jdbc:mysql://localhost:3306/b 
    -Dliquibase.username=user -Dliquibase.password=bbb 
    -Dliquibase.referenceusername=user 
    -Dliquibase.referencepassword=bbb 
    -Dliquibase.changelogfile=changelog.yaml 
    -Dliquibase.referencedriver=liquibase.ext.hibernate.database.connection.HibernateDriver 
    -Dliquibase.driver=org.mariadb.jdbc.Driver

The diffchangelogfile that is generated does not have any comparison between the 2 databases. I already checked in dbeaver and the 2 databases are in fact different. Am I missing something here ?