The error message you are getting is a result of Git still thinking that you have not resolved the merge conflicts. In fact, you already have, but you need to tell Git that you have done this by adding the resolved files to the index.
This has the side effect that you could actually just add the files without resolving the conflicts, and Git would still think that you have. So you should be diligent in making sure that you have really resolved the conflicts. You could even run the build and test the code before you commit.