Android Question Error with DropBoxHttpApi [SOLVED]

Dbx.Upload(Direct,"primanota.s3db","/","primanota.s3db")

main_dupload_click (java line: 3368)
java.lang.NoClassDefFoundError: Failed resolution of: Lokhttp3/RequestBody;
at anywheresoftware.b4a.samples.httputils2.httpjob._class_globals(httpjob.java:70)
at java.lang.reflect.Method.invoke(Native Method)
at anywheresoftware.b4a.BA.raiseEvent2(BA.java:186)
at anywheresoftware.b4a.samples.httputils2.httpjob.innerInitialize(httpjob.java:23)
at anywheresoftware.b4a.samples.httputils2.httpjob._initialize(httpjob.java:238)
at b4a.example.dropbox._vvvvvvvvvv0(dropbox.java:2593)
at it.tecnomedia.primanotapro.main._dupload_click(main.java:3368)
at java.lang.reflect.Method.invoke(Native Method)
at anywheresoftware.b4a.BA.raiseEvent2(BA.java:186)
at anywheresoftware.b4a.BA.raiseEvent2(BA.java:170)
at anywheresoftware.b4a.BA.raiseEvent(BA.java:166)
at anywheresoftware.b4a.objects.ViewWrapper$1.onClick(ViewWrapper.java:80)
at android.view.View.performClick(View.java:5646)
at android.view.View$PerformClick.run(View.java:22459)
at android.os.Handler.handleCallback(Handler.java:761)
at android.os.Handler.dispatchMessage(Handler.java:98)
at android.os.Looper.loop(Looper.java:156)
at android.app.ActivityThread.main(ActivityThread.java:6523)

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