单独运行此程序，预期是发送失败，但现实的日志是成功发送和失败交替出现

日志如下

I got ticker
Ok(100)
I got ticker
Err(Os { code: 111, kind: ConnectionRefused, message: "Connection refused" })
I got ticker
Ok(100)
I got ticker
Err(Os { code: 111, kind: ConnectionRefused, message: "Connection refused" })

code:

use prost::Message as prostMessage;
use std::time::Duration;
use std::{io, net::SocketAddr, sync::Arc};
use tip_proto::pb::communication::{CommunicationData, HandoverData, Scenes};
use tokio::time;
use tokio::{net::UdpSocket, sync::mpsc};

#[tokio::main]
async fn main() -> io::Result<()> {
    let sock = UdpSocket::bind("0.0.0.0:9091").await?;

    let remote_addr = "127.0.0.1:9090";
    sock.connect(remote_addr).await?;
    let r = Arc::new(sock);
    let s = r.clone();

    tokio::spawn(async move {
        let buf = [1; 100];
        let mut ticker = time::interval(Duration::from_secs(5));
        loop {
            ticker.tick().await;
            // do_something().await;
            println!("I got ticker");
            let len = s.send(&buf[..]).await;
            println!("{:?}", len);
        }
    });

    let mut buf = [0; 1024];
    loop {
        let len = r.recv(&mut buf).await?;
        println!("{:?} bytes received", len);
        println!("buf is {:?}", &buf[..len]);
        let mut communication_data: CommunicationData =
            CommunicationData::decode(&buf[..len]).unwrap();
   
        println!("{:?}", &communication_data);
    }
}