Android Native call example not working, mTransportAgent.addHelperServer Failed

g_main_context_push_thread_default: assertion 'acquired_context' failed
g_main_context_pop_thread_default: assertion 'stack != NULL' failed

`
mTransportAgent = new TransportAgent(isInitiator);

```
for (RtcConfig.HelperServer helperServer : mConfig.getHelperServers()) {
mTransportAgent.addHelperServer(
helperServer.getType(),
helperServer.getAddress(),
helperServer.getPort(),
helperServer.getUsername(),
helperServer.getPassword()
);
}
```

`

`
void owr_transport_agent_add_helper_server(OwrTransportAgent *transport_agent,
OwrHelperServerType type, const gchar *address, guint port,
const gchar *username, const gchar *password)
{
GHashTable *helper_server_info;
GResolver *resolver;

```
g_return_if_fail(OWR_IS_TRANSPORT_AGENT(transport_agent));

transport_agent->priv->deferred_helper_server_adds++;

helper_server_info = _owr_create_schedule_table(OWR_MESSAGE_ORIGIN(transport_agent));
g_hash_table_insert(helper_server_info, "transport_agent", transport_agent);
g_hash_table_insert(helper_server_info, "type", GUINT_TO_POINTER(type));
g_hash_table_insert(helper_server_info, "port", GUINT_TO_POINTER(port));
if (username)
g_hash_table_insert(helper_server_info, "username", g_strdup(username));
if (password)
g_hash_table_insert(helper_server_info, "password", g_strdup(password));

g_object_ref(transport_agent);
resolver = g_resolver_get_default();
g_main_context_push_thread_default(_owr_get_main_context());
g_resolver_lookup_by_name_async(resolver, address, NULL,
(GAsyncReadyCallback)add_helper_server_info, helper_server_info);
g_main_context_pop_thread_default(_owr_get_main_context());
g_object_unref(resolver);
```

}

`

can't debug with it? what should I do ? plz help me find out