Using diff changelog to compare snapshot and current DB Oracle

I am working on generating a changelog which is basically a diff changelog of snapshot and current logged in database. I am using sqlcl.
When I try
lb dic -reur=“offline:oracle?snapshot=mySnapshot.json”
the response requests for reference username and reference password as well. What does these mean here? As for a snaphot do we still need to provide the username and password ?
I provided the username and password and the next issue is
No suitable driver found for offline:oracle?snapshot=mySnapshot.json

I tried looking for this but could not get a working solution.

I also see couple of parameters changed when working on liquibase and comparing with the documentation. For example,
diff changelog has a parameter --url in the documentation while the same does not exist while using. Please help.