How to Fix "Getter isn't defined for the Class" (Flutter-Flutterflow)

Question

I'm using Flutterflow which is basically a drag and drop system for coding flutter, i implemented an API Call using Google Books API to a ListView Widget, The Flutterflow Debugger itself shows no errors but on run i get the error "lib/pages/library/makearequest/makearequest_widget.dart:462:45: Error: The getter 'llvLibraryBookRequestResponse' isn't defined for the class '_MakearequestWidgetState'.

• '_MakearequestWidgetState' is from 'package:afit_student_companion/pages/library/makearequest/makearequest_widget.dart' ('lib/pages/library/makearequest/makearequest_widget.dart')."

The error is a compilation error from the make request class How can i go about fixing this issue with regards to flutter Here is a sample of the code portion

LibraryBookRequestCall.call(
                                searchTerm: _model.textController.text,
                              ).then((llvLibraryBookRequestResponse) {
                                final pageItems = (getJsonField(
                                          llvLibraryBookRequestResponse
                                              .jsonBody,
                                          r'''$.items''',
                                        ) ??
                                        [])
                                    .take(15 - nextPageMarker.numItems)
                                    .toList() as List;
                                final newNumItems =
                                    nextPageMarker.numItems + pageItems.length;
                                _model.pagingController!.appendPage(
                                  pageItems,
                                  (pageItems.length > 0) && newNumItems < 15
                                      ? ApiPagingParams(
                                          nextPageNumber:
                                              nextPageMarker.nextPageNumber + 1,
                                          numItems: newNumItems,
                                          lastResponse:
                                              llvLibraryBookRequestResponse,
                                        )
                                      : null,
                                );
                              });
                            });
                            return _model.pagingController!;
                          }(),
                          padding: EdgeInsets.zero,
                          reverse: false,
                          scrollDirection: Axis.vertical,
                          builderDelegate: PagedChildBuilderDelegate<dynamic>(
                            // Customize what your widget looks like when it's loading the first page.
                            firstPageProgressIndicatorBuilder: (_) => Center(
                              child: SizedBox(
                                width: 40,
                                height: 40,
                                child: CircularProgressIndicator(
                                  color: FlutterFlowTheme.of(context).primary,
                                ),
                              ),
                            ),

The Full Code Sample for the page can be found on JustPasteIt

I tried following the suggestions from this thread Stack Overflow Thread and Stack Overflow Thread as the issue being solved is similiar to mine, but i couldnt understand how to implement this for myself. I need more clearer explanantions. Thanks