HarmonyOS 鸿蒙Next geoLocationManager.off不生效

请问使用这个代码获取持续位置信息，点击关闭时候 geoLocationManager.off 没有生效，应该怎么处理？

 OpenContinuosLocation() {

    let request: geoLocationManager.ContinuousLocationRequest = {

      'interval': 1,

      'locationScenario': geoLocationManager.UserActivityScenario.NAVIGATION

    }

    let locationCallback = (location: geoLocationManager.Location): void => {

      console.log('定位信息: ' + JSON.stringify(location));

    };

    try {

      geoLocationManager.on('locationChange', request, locationCallback);

    } catch (err) {

      console.error("errCode:" + JSON.stringify(err));

    }

  }

  /**

   * 关闭持续定位

   */

  ClosedContinuosLocation() {

    geoLocationManager.off('locationChange', (loca: geoLocationManager.Location) => {

      console.log("持续定位关闭");

      console.log("最后一次定位" + json.stringify(loca));

    })

  }

  build() {

    Column() {

      Button("开启持续定位").width(220).height(50)

        .margin({ bottom: 40 })

        .onClick(() => {

          this.OpenContinuosLocation()

        })

      Button("关闭持续定位").width(220).height(50)

        .margin({ bottom: 40 })

        .onClick(() => {

          this.ClosedContinuosLocation()

        })

    }

    .height('100%')

    .width('100%')

    .justifyContent(FlexAlign.Center)

  }