jenkins run infinite loop after an update

Question

my jenkins pipeline already worked, but after installing an Update it seems i received some problems. When i run this code

pipeline {
    agent {
        label 'free_machine'
    }
    stages {
        stage('Build') {
            steps {
                echo 'Building..'
            }
        }
        stage('Test') {
            steps {
                echo 'Testing..'
            }
        }
        stage('Deploy') {
            steps {
                echo 'Deploying....'
            }
        }
    }
}

then my pipeline will make an infinite loop and it seems it cannot connect to remote machine. I added the console output in the image. Also it seems that the agent is online. See picture agents. Does someone know what a possible error can be?

agents console output