extract method does not work with implicit return at the end

[stephane-archer]

                  onTap: () async {
                    final LutFoldersState lutFoldersState =
                        await ref.read(lutFoldersProvider.future);
                    ref.read(selectedLutFolderProvider.notifier).state = null;
                    final LutPreviewImagesChangeNotifier
                        lutPreviewImagesChangeNotifier =
                        ref.read(lutPreviewImagesProvider);
                    final String? refImagePath =
                        ref.read(refImgagePathProvider);
                    if (refImagePath == null) {
                      return;
                    }
                    final Resolution? resolution =
                        await ref.read(refImageResolutionProvider.future);
                    if (resolution == null) {
                      return;
                    }
                    await lutPreviewImagesChangeNotifier.cleanAndComputeLuts(
                      lutFoldersState.lutFoldersDir,
                      refImagePath,
                      getPreviewResolution(resolution),
                    );
                  },

extract method by selecting all the code in between the braces {}
Selected statements contain a return statement, but not all possible execution flows exit. Semantics may not be preserved.

just add a return at the end and the code works.
the extraction should work without the return at the end