Ubuntu 20.04.3 autoinstall Network Issue dhcp

Currently I have a small ssh network problem. I use an Ubuntu 20.4 Server Edition incl. autoinstall. I removed the network configuration from my user-data file because it should be better for the installation to select the adapters itself. Now I have the problem that after the first reboot my packer script cannot connect to ssh.

Only after entering the command dhclient -r and dhclient the packer script connected successfully with my Ubuntu installation.

user-data File:

#cloud-config
 autoinstall:
  version: 1
  early-commands:
    - systemctl stop ssh
  locale: en_US
  apt:
    geoip: true
  keyboard:
    layout: en
    variant: us
  storage:
    grub:
      reorder_uefi: False
    config:
    - {ptable: gpt, path: /dev/vda, preserve: false, name: '', grub_device: false,
      type: disk, id: disk-vda}
    - {device: disk-vda, size: 536870912, wipe: superblock, flag: boot, number: 1,
      preserve: false, grub_device: true, type: partition, id: partition-vda1}
    - {fstype: fat32, volume: partition-vda1, preserve: false, type: format, id: format-2}
    - {device: disk-vda, size: 1073741824, wipe: superblock, flag: linux, number: 2,
      preserve: false, grub_device: false, type: partition, id: partition-vda2}
    - {fstype: ext4, volume: partition-vda2, preserve: false, type: format, id: format-0}
    - {device: disk-vda, size: -1, flag: linux, number: 3, preserve: false,
      grub_device: false, type: partition, id: partition-vda3}
    - name: vg-0
      devices: [partition-vda3]
      preserve: false
      type: lvm_volgroup
      id: lvm-volgroup-vg-0
    - {name: lv-root, volgroup: lvm-volgroup-vg-0, size: 100%, preserve: false,
      type: lvm_partition, id: lvm-partition-lv-root}
    - {fstype: ext4, volume: lvm-partition-lv-root, preserve: false, type: format,
      id: format-1}
    - {device: format-1, path: /, type: mount, id: mount-2}
    - {device: format-0, path: /boot, type: mount, id: mount-1}
    - {device: format-2, path: /boot/efi, type: mount, id: mount-3}
  identity:
    hostname: ubuntu
    username: ubuntu
    # pass is ubuntu
    password: $6$rounds=4096$8dkK1P/oE$2DGKKt0wLlTVJ7USY.0jN9du8FetmEr51yjPyeiR.zKE3DGFcitNL/nF1l62BLJNR87lQZixObuXYny.Mf17K1
  ssh:
    install-server: yes
  packages:
    - network-manager
    - vim
    - tmux
    - curl
  package_update: true
  package_upgrade: true
  user-data:
    disable_root: false
  late-commands:
    - echo 'ubuntu ALL=(ALL) NOPASSWD:ALL' > /target/etc/sudoers.d/ubuntu
    # Changing from networkd to NetworkManager
    # move existing config out of the way
    - find /target/etc/netplan/ -name "*.yaml" -exec sh -c 'mv "$1" "$1-orig"' _ {} \;
    # Create a new netplan and enable it
    - |
      cat <<EOF | sudo tee /target/etc/netplan/01-netcfg.yaml
      network:
        version: 2
        renderer: NetworkManager
      EOF
    - curtin in-target --target /target netplan generate
    - curtin in-target --target /target netplan apply
    - curtin in-target --target /target systemctl enable NetworkManager.service
    - dhclient -r
    - sleep 10s
    - dhclient
    - sleep 10s