Error using REST mock service

Hi

I am trying to make a REST mock service but I run in the next problem. Who can help me?

-Open a new REST project
-Copy the url with parameters in the URL: field
-Add a new Mockservice to the project
-The project has no operations
-When I try to add an Operation I get the next error message:

“No unique operations to mock in project!”

What am I doing wrong?


Greetings

Roger