Exception on starting a Navigation

[HeftyCoder]

On Android, starting a navigation causes this exception to be thrown:
Attempt to invoke virtual method 'es.situm.sdk.navigation.ExternalNavigation$MessageType es.situm.sdk.navigation.ExternalNavigation.getMessageType()' on a null object reference

I've attempted to clear the cache/storage of the application and reinstall. It may only temporarily fix the issue. I've been trying this on a test building with some simulated beacons. The code is from the quickstart sample app

I'm enclosing the settings.gradle file (I've changed com.android.application version to 8.3.0 else it wouldn't compile) and also the build.gradle file (changed ndkVersion ="25.1.8937393" else it wouldn't build).

settings.gradle

pluginManagement {
    def flutterSdkPath = {
        def properties = new Properties()
        file("local.properties").withInputStream { properties.load(it) }
        def flutterSdkPath = properties.getProperty("flutter.sdk")
        assert flutterSdkPath != null, "flutter.sdk not set in local.properties"
        return flutterSdkPath
    }()

    includeBuild("$flutterSdkPath/packages/flutter_tools/gradle")

    repositories {
        google()
        mavenCentral()
        gradlePluginPortal()
    }
}

plugins {
    id "dev.flutter.flutter-plugin-loader" version "1.0.0"
    id "com.android.application" version "8.3.0" apply false
    id "org.jetbrains.kotlin.android" version "1.8.22" apply false
}

include ":app"

build.gradle

plugins {
    id "com.android.application"
    id "kotlin-android"
    // The Flutter Gradle Plugin must be applied after the Android and Kotlin Gradle plugins.
    id "dev.flutter.flutter-gradle-plugin"
}

android {
    namespace = "com.example.test_app"
    compileSdk = flutter.compileSdkVersion
    compileSdkVersion 34
    ndkVersion = "25.1.8937393"

    compileOptions {
        sourceCompatibility = JavaVersion.VERSION_1_8
        targetCompatibility = JavaVersion.VERSION_1_8
    }

    kotlinOptions {
        jvmTarget = JavaVersion.VERSION_1_8
    }

    defaultConfig {
        // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
        applicationId = "com.example.test_app"
        // You can update the following values to match your application needs.
        // For more information, see: https://flutter.dev/to/review-gradle-config.
        minSdk = 21
        targetSdk = 33
        versionCode = flutter.versionCode
        versionName = flutter.versionName
    }

    buildTypes {
        release {
            // TODO: Add your own signing config for the release build.
            // Signing with the debug keys for now, so `flutter run --release` works.
            signingConfig = signingConfigs.debug
        }
    }
}

flutter {
    source = "../.."
}