Meter values not received

[solanu]

I have the following code and I don't receive meter values:

package main

import (
    "errors"
    "fmt"
    "log"
    "os"
    "strings"
    "time"

    "github.com/voltbras/go-ocpp"
    "github.com/voltbras/go-ocpp/cs"
    "github.com/voltbras/go-ocpp/messages/v1x/cpreq"
    "github.com/voltbras/go-ocpp/messages/v1x/cpresp"
)

func main() {
    ocpp.SetDebugLogger(log.New(os.Stdout, "DEBUG:", log.Ltime))
    ocpp.SetErrorLogger(log.New(os.Stderr, "ERROR:", log.Ltime))
    csys := cs.New()
    go csys.Run(":21022", func(req cpreq.ChargePointRequest, metadata cs.ChargePointRequestMetadata) (cpresp.ChargePointResponse, error) {
        fmt.Printf("EXAMPLE(MAIN): Request from %s\n", metadata.ChargePointID)
        fmt.Printf(">>>>>>> %v\n", req.Action())
        switch req := req.(type) {
        case *cpreq.BootNotification:
            return &cpresp.BootNotification{
                Status:      "Accepted",
                CurrentTime: time.Now(),
                Interval:    60,
            }, nil
        case *cpreq.Heartbeat:
            return &cpresp.Heartbeat{CurrentTime: time.Now()}, nil
        case *cpreq.MeterValues:
            fmt.Println("This message is not displayed")
            fmt.Printf("METADATA %#v\n", metadata)
            fmt.Printf("REQ - metervalue: %#v\n", req.MeterValue)
            return &cpresp.MeterValues{}, nil
        case *cpreq.StatusNotification:
            fmt.Println("This works " + req.Status)
            if req.Status != "Available" {
                // chargepoint is unavailable
            }
            return &cpresp.StatusNotification{}, nil

        default:
            fmt.Printf("EXAMPLE(MAIN): action not supported: %s\n", req.Action())
            return nil, errors.New("Response not supported")
        }

    })
    select {}
}

My charge point is configure to send meter values.