Another reason that can caused the Release Automation perspective is not shown in ARA is the login user does not exist in ARA database. We can easily identify this by check the ECC logs:
Caused by: java.lang.Throwable: Deployment Manager error: User
100
/API1/API does not exist or inactive
...
15
common frames omitted
We can also check if the login user is exist in our ARA Database by using ImportExportCLI.exe
The command to export an User:
C:\Automic\Tools\ARA\Utilities\ImportExportCLI>ImportExportCLI.exe EXPORT export -con http://vvnsatara04/ARA -usr AUTOMIC/100/AUTOMIC/AUTOMIC -pwd automic -mt user -format xml -fi C:\exportUser.xml -where "system_name eq '100/API1/API'"
So to move forward with this issue, you should use an existing login user to login ARA or create a new one.