QM application is not accessible during Prod Copy to Preprod instance

We are planning to perform server rename with the production data copy. When we are accessing QM application we see below error in UI 

{"nestedError":{"errorClass":"com.ibm.team.repository.common.PermissionDeniedException","errorMessage":"Permission Denied","errorCode":null},"errorClass":"java.lang.RuntimeException","errorMessage":"com.ibm.team.repository.common.PermissionDeniedException: Permission Denied","errorCode":500}

Error in QM Log file

ERROR m.team.integration.auth.sdk.AuthenticatorException [TID: 880FBFFC] - CRJSA0008E The application could not authenticate with another application by using a bearer token. This error was returned: "null"
Explanation: The application attempted to contact another application with a bearer token but was unable to authenticate.
User Action: For details about the cause of the error, check the log files for both the sending and the receiving applications.

Any help on the above issue will be much appreciated