I have followed the MSDN article to give app permission to the Workflow and added the app step in the Workflow with elevated privilege. Under this step, made a web service call to
{web url}/_api/SP.UserProfiles.PeopleManager/GetUserProfilePropertyFor(accountName=@v,propertyName='Manager')?@v='{AccountId}'
However, got the same System.UnauthorizedAccessException
message, as mentioned in the following question.
Can somebody help identify where the issue is?