Error querying the server PAUSE_IF_NO_PLAYERS

Compose file:

services:
  mc:
    image: itzg/minecraft-server:java8
    container_name: crash-landing
    restart: unless-stopped
    ports:
        - "25565:25565"
    environment:
        EULA: "true"
        VERSION: "1.6.4"
        TYPE: "CURSEFORGE"
        CF_SERVER_MOD: "/modpack/CrashLandingServer.zip"
        MOTD: "Crash landing chi legge"
        MAX_MEMORY: 4G
        
        ENABLE_RCON: "true"
        RCON_PASSWORD: "***"
        
        OVERRIDE_SERVER_PROPERTIES: "true"
    volumes:
        - ./data:/data
        - ./modpack:/modpack
  backups:
    image: itzg/mc-backup
    container_name: crash-landing-BK
    environment:
        DEBUG: TRUE
        RCON_HOST: "mc"
        RCON_PASSWORD: "***"
        
        BACKUP_INTERVAL: "2m"
        PAUSE_IF_NO_PLAYERS: "true"
        PLAYERS_ONLINE_CHECK_INTERVAL: "5m"
        PRE_BACKUP_SCRIPT: echo "Backup Started!"
        POST_BACKUP_SCRIPT: echo "Backup from server to mc-backup finished"
    volumes:
        # mount the same volume used by server, but read-only
        - ./data:/data:ro
        # use a host attached directory so that it in turn can be backed up
        # to external/cloud storage
        - ./mc-backups:/backups

Error log:

crash-landing-BK  | + true
crash-landing-BK  | + is_paused
crash-landing-BK  | + [[ -e /data/.paused ]]
crash-landing-BK  | ++ mc-monitor status --host mc --port 25565 --show-player-count
crash-landing     | 2024-10-15 09:43:42 [INFO] [STDERR] java.io.IOException: Bad packet id 99
crash-landing     | 2024-10-15 09:43:42 [INFO] [STDERR]         at net.minecraft.network.packet.Packet.func_73272_a(Packet.java:149)
crash-landing     | 2024-10-15 09:43:42 [INFO] [STDERR]         at net.minecraft.network.TcpConnection.func_74447_i(TcpConnection.java:325)
crash-landing     | 2024-10-15 09:43:42 [INFO] [STDERR]         at net.minecraft.network.TcpConnection.func_74450_c(TcpConnection.java:549)
crash-landing     | 2024-10-15 09:43:42 [INFO] [STDERR]         at net.minecraft.network.TcpReaderThread.run(SourceFile:94)
crash-landing-BK  | + PLAYERS_ONLINE='2024-10-15T09:43:42.744Z  DEBUG   mc-monitor/java_status.go:82    pinging
crash-landing-BK  | 2024-10-15T09:43:42.747Z    DEBUG   mc-monitor/java_status.go:85    ping returned   {"error": "read tcp 172.19.0.2:33806->172.19.0.3:25565: read: connection reset by peer", "info": null}
crash-landing-BK  | failed to ping mc:25565 : read tcp 172.19.0.2:33806->172.19.0.3:25565: read: connection reset by peer'
crash-landing-BK  | + log ERROR 'Error querying the server, waiting 5m...'
crash-landing-BK  | + local oldState
crash-landing-BK  | ++ shopt -po xtrace
crash-landing-BK  | + oldState='set -o xtrace'
crash-landing-BK  | + shopt -u -o xtrace
crash-landing-BK  | 2024-10-15T09:43:42+0000 ERROR Error querying the server, waiting 5m...
crash-landing-BK  | + sleep 5m
crash-landing     | 2024-10-15 09:43:42 [INFO] [Minecraft-Server] Disconnecting /172.19.0.2:33806: Protocol error
crash-landing     | 2024-10-15 09:43:42 [INFO] [Minecraft-Server] /172.19.0.2:33806 lost connection

What i am doing wrong?