Vagrant NFS share no longer working

The following Vagrantfile used to work, and now it doesn't.

This is an Ubuntu 20.04 install, and I'm using Virtualbox.

Vagrant.configure('2') do |config|
  # Set Box
  config.vm.box = "generic/ubuntu2004"
  # Set hostname
  config.vm.hostname = "xxx"
  config.vm.define "xxx"
  config.vm.provider :virtualbox do |vb|
    vb.name = "xxx"
  end

  # Prevent vagrant-vbguests from being auto updated, this is time consuming and causes version mismatch with host
  if Vagrant.has_plugin? "vagrant-vbguest"
    config.vbguest.no_install  = false
    config.vbguest.auto_update = false
    config.vbguest.no_remote   = true
  end

  # Enable vagrant-bindfs support, if the plugin is installed
  # see https://github.com/gael-ian/vagrant-bindfs for details
  if Vagrant.has_plugin?("vagrant-bindfs")
    # The bindfs option has one more option, and the /var/nfs
    # is where the the folder is synced then it binds it to the
    # guest_path after.
    #
    # Ubuntu 22.04 has UDP disabled for NFS mounts
    # https://discourse.ubuntu.com/t/jammy-jellyfish-release-notes/24668

    config.vm.synced_folder ".", "/var/nfs", type: "nfs", nfs_udp: false

    # This uses uid and gid of the user that started vagrant.
    config.nfs.map_uid = Process.uid
    config.nfs.map_gid = Process.gid

    config.bindfs.bind_folder "/var/nfs", "/vagrant",
      perms: 'u=rwX:g=rwD',
      u: 'vagrant',
      g: 'www-data',
      o: 'nonempty'
  else
    # Enable NFS file system
    config.vm.synced_folder ".", "/vagrant", type: "nfs",  nfs_udp: false

    # This uses uid and gid of the user that started vagrant.
    config.nfs.map_uid = Process.uid
    config.nfs.map_gid = Process.gid
  end

  # This uses the vagrant-disksize support, if the plugin is installed
  if Vagrant.has_plugin?("vagrant-disksize")
    config.disksize.size = '20GB'
  end

  # Configure RAM
  config.vm.provider "virtualbox" do |vb|
    # Customize the amount of memory on the VM:
    vb.memory = "4096"
    vb.cpus = 2
  end

  # Specify private network
  config.vm.network "private_network", ip: "192.168.56.10"
  # Port requires for postgres
  config.vm.network :forwarded_port, guest: 5432, host: 5432
  config.vm.network :forwarded_port, guest: 80, host: 8080

  # Enable provisioning with a shell script.
  # config.vm.provision :shell, :path => "local/bootstrap.sh"

end

The error I get is:

The following SSH command responded with a non-zero exit status.
Vagrant assumes that this means the command failed!

mount -o vers=3 192.168.56.1:/home/steve/Projects/ze /var/nfs

Stdout from the command:

mount.nfs: requested NFS version or transport protocol is not supported

I always run vagrant destroy then vagrant up on each test. What I've done:

• Allowed the vbguests to run and update
• Tried NFS version 4
• Tried it without NFS (it completes but the installation doesn't work)
• Tried "192.168.56.1" as the host IP
• Initially on Vagrant 2.3.4, upgraded to 2.3.7 (and tried everything again)
• Tried to do the mount inside the VM, results typically this:

sudo mount -o vers=3 192.168.56.1:/home/steve/Projects/ze /var/nfs -v

mount.nfs: timeout set for Mon Jul  3 09:06:25 2023
mount.nfs: trying text-based options 'vers=3,addr=192.168.56.1'
mount.nfs: prog 100003, trying vers=3, prot=6
mount.nfs: portmap query retrying: RPC: Program not registered
mount.nfs: prog 100003, trying vers=3, prot=17
mount.nfs: portmap query failed: RPC: Program not registered
mount.nfs: requested NFS version or transport protocol is not supported

I'm losing the will to live, so any help would be appreciated.