some.kt

E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.mandarine.sdk.sample, PID: 32562
    java.lang.NoClassDefFoundError: Failed resolution of: Lcom/mandarine/sdk/connector/ProvidersConnector;
        at com.mandarine.sdk.network.SERequestManager.fetchProviders(SERequestManager.java:68)
        at com.mandarine.sdk.sample.features.ConnectionsFragment.fetchAndShowProviders(ConnectionsFragment.java:191)
        at com.mandarine.sdk.sample.features.ConnectionsFragment.onClick(ConnectionsFragment.java:129)
        at android.view.View.performClick(View.java:6304)
        at android.view.View$PerformClick.run(View.java:24803)
        at android.os.Handler.handleCallback(Handler.java:794)
        at android.os.Handler.dispatchMessage(Handler.java:99)
        at android.os.Looper.loop(Looper.java:176)
        at android.app.ActivityThread.main(ActivityThread.java:6635)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:823)
     Caused by: java.lang.ClassNotFoundException: com.mandarine.
.connector.ProvidersConnector
        at java.lang.VMClassLoader.findLoadedClass(Native Method)
        at java.lang.ClassLoader.findLoadedClass(ClassLoader.java:738)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:363)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:312)
        at com.mandarine.sdk.network.SERequestManager.fetchProviders(SERequestManager.java:68) 
        at com.mandarine.sdk.sample.features.ConnectionsFragment.fetchAndShowProviders(ConnectionsFragment.java:191) 
        at com.mandarine.sdk.sample.features.ConnectionsFragment.onClick(ConnectionsFragment.java:129) 
        at android.view.View.performClick(View.java:6304) 
        at android.view.View$PerformClick.run(View.java:24803) 
        at android.os.Handler.handleCallback(Handler.java:794) 
        at android.os.Handler.dispatchMessage(Handler.java:99) 
        at android.os.Looper.loop(Looper.java:176) 
        at android.app.ActivityThread.main(ActivityThread.java:6635) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:823) 
     Caused by: java.lang.NoClassDefFoundError: Failed resolution of: Lretrofit2/Callback;
        at com.mandarine.sdk.network.SERequestManager.fetchProviders(SERequestManager.java:68) 
        at com.mandarine.sdk.sample.features.ConnectionsFragment.fetchAndShowProviders(ConnectionsFragment.java:191) 
        at com.mandarine.sdk.sample.features.ConnectionsFragment.onClick(ConnectionsFragment.java:129) 
        at android.view.View.performClick(View.java:6304) 
        at android.view.View$PerformClick.run(View.java:24803) 
        at android.os.Handler.handleCallback(Handler.java:794) 
        at android.os.Handler.dispatchMessage(Handler.java:99) 
        at android.os.Looper.loop(Looper.java:176) 
        at android.app.ActivityThread.main(ActivityThread.java:6635) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:823) 
     Caused by: java.lang.ClassNotFoundException: Didn't find class "retrofit2.Callback" on path: DexPathList[[zip file "/data/app/com.mandarine.sdk.sample-oOr6gZ8OfbioK8WSa02OYA==/base.apk"],nativeLibraryDirectories=[/data/app/com.mandarine.sdk.sample-oOr6gZ8OfbioK8WSa02OYA==/lib/arm64, /system/lib64, /vendor/lib64]]
        at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:125)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:379)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:312)
        at com.mandarine.sdk.network.SERequestManager.fetchProviders(SERequestManager.java:68) 
        at com.mandarine.sdk.sample.features.ConnectionsFragment.fetchAndShowProviders(ConnectionsFragment.java:191) 
        at com.mandarine.sdk.sample.features.ConnectionsFragment.onClick(ConnectionsFragment.java:129) 
        at android.view.View.performClick(View.java:6304) 
        at android.view.View$PerformClick.run(View.java:24803) 
        at android.os.Handler.handleCallback(Handler.java:794) 
        at android.os.Handler.dispatchMessage(Handler.java:99) 
        at android.os.Looper.loop(Looper.java:176) 
        at android.app.ActivityThread.main(ActivityThread.java:6635) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:823)