Shape builder tool

Hello, I am trying to create a logo with the shape builder tool. As you can see from my screenshot, I want to keep the green parts and remove the red parts.

Unfortunately, the shape builder too is not working even after I have selected all the objects. (There is a cross symbol on the cursor)

The heart and small circles were constructed with object>repeat>mirror and object>repeat>radial respectively. It might be the reason why it is not working. 

Please help, thank you very much.