restful service of another database is not working

I am trying to setup a restful service for a database which is duplicated from production (Oracle Database 19c - 19.0.0.0.0)

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in production server, the database rest service and its apex application is working fine.

now in uat server, I created another apex application and it is also working fine with a dummy apex database through rest service. the endpoint is returning data

http://192.168.xx.xxx:8080/ords/schemaalias1/modulename1/handler1/

now, I duplicated a database from production. From my understanding, I will need to create connection between uat ords and this duplicated database.

since the ords version in production (21.1.3.r1531102) is lower than uat server (20.4.1.r0131644) . so I dropped below users and roles