Opentelemetry metrics can not display in kibana

Hi all,

I use the APM Go with OpenTelemetry API as bellow link:

Agenthttps://www.elastic.co/guide/en/apm/agent/go/current/opentelemetry.html#opentelemetry-metrics-init

And I want to export my custom metric to kibana, but not found the metric, here codes as below:
exporter, _ := apmotel.NewGatherer()

// Configure OpenTelemetry
provider1 := metric.NewMeterProvider(metric.WithReader(exporter))
otel.SetMeterProvider(provider1)
// Configure the Elastic APM
apm.DefaultTracer().RegisterMetricsGatherer(exporter)

meter := provider1.Meter("my_application")
counter, _ := meter.Float64Counter("metric_called")
counter.Add(context.TODO(), 1)

the version info as below which i used:
kibana v7.17.5 , elastic apm v7.17.5, Elasticsearch v7.17.5