On Sandbox environment (Microsoft hosted), we did db refresh from PROD. We have Retail (Commerce) application in use.
We did Channel db config, device activation and ran full sync from Headquarter to RCSU. We created a new channel profile and provided required URLs for commerce server, media server and cloud POS.
However, during channel profile configuration, we could not change Default channel profile URLs as they are shown grayed out. We created our own channel profile and set the URLs there. Now I don't understand one thing here is how this channel profile is linked with channel DB.

Look at the below CPOS connection issue.
We could login and active the device using CPOS, but it could not go further and failed at environment configuration step. I feel that this CPOS is still trying to connect to Default Channel DB and not to our newly created RCSU database.

Can someone please help to understand what is required here so that CPOS connects to our own RCSU database and not Default one?