command executed successfully but no luck. Pull requests didn't get generated. Here is the command which I fired.
curl -u myUserName:myPwd -H "Content-Type: application/json" https://bitbucket.org/rest/api/1.0/projects/myProject/repos/myCore/pull-requests -X POST --data '{"title":"merge","description":"merge","fromRef":{"id":"refs/heads/testBranch","repository":{"slug":"myCore","name":null,"project":{"key":"testBranch"}}},"toRef":{"id":"refs/heads/toBranch","repository":{"slug":"myRepo","name":null,"project":{"key":"testBranch"}}}}'