request.AdapTo() giving null values while doing Unit testing for sling models

hi I have the following model class :

@Model(
    adaptables = SlingHttpServletRequest.class,
    defaultInjectionStrategy = DefaultInjectionStrategy.OPTIONAL)
public class LocationsModel extends ComponentModel implements Validatable {
  private static final Logger log = LoggerFactory.getLogger(LocationsModel.class);
  private static final String CSS_CLASS_NAME = "locations";

  @OSGiService
  private GoogleMapAPIConfiguration mapAPIConfiguration;

  @ValueMapValue
  private String title;

  @ValueMapValue
  private int zoomLevel;
  
  @ChildResourceFromRequest
  private final List<LocationItem> locations = emptyList();

  private String locationsJson;
  private String key;

  public LocationsModel() {
  }

  @PostConstruct
  protected void init() {
    if (mapAPIConfiguration != null) {
      this.key = mapAPIConfiguration.getKey();
    }

    try {
      this.locationsJson = new ObjectMapper().writeValueAsString(this.locations);
    } catch (JsonProcessingException ex) {
      log.error("Unable to generate locations to JSON string", ex);
    }
  }

  @Nonnull
  @Override
  public String getCssClassName() {
    return CSS_CLASS_NAME;
  }

  @Override
  public boolean isValid() {
    return StringUtils.isNotEmpty(this.key) && !this.locations.isEmpty();
  }

  public String getTitle() {
    return this.title;
  }

  @Nonnull
  public List<LocationItem> getLocations() {
    return this.locations;
  }

  public String getLocationsJson() {
    return this.locationsJson;
  }

  public int getZoomLevel() {
    return this.zoomLevel;
  }

  public String getKey() {
    return this.key;
  }
}

and the test class is :

@ExtendWith({AemContextExtension.class, MockitoExtension.class})
class LocationsModelTest {

    Private final AemContext ctx = new AemContext();
    public LocationsModel locationsModel;
    @BeforeEach
    void setUp() throws Exception {
        ctx.addModelsForClasses(LocationsModel.class);
        ctx.load().json("/locations/LocationsModelTest.json","/content");
    }
    @Test
    void getZoomLevel() {
        ctx.currentResource("/content/location");
        System.out.println("ctx "+ctx.request().adaptTo(LocationsModel.class));
        locationsModel=ctx.request().adaptTo(LocationsModel.class);             // GETTING NULL VALUE HERE
        
        int expected = 10;
        int actual = locationsModel.getZoomLevel();
        locationsModel.getLocations();
        assertEquals(expected,actual);
    } 
}

I am not able to find out why this line is giving null value ..

the paths are correct and I have provided the JSON also in the same path as mentioned but somehow getting null  in " locationsModel=ctx.request().adaptTo(LocationsModel.class);" 

please help me resolve the issue

Thank you