Second FFU attempt fails with Error: '4' from left operand of 'in' expression

Issue

• The first rollback attempt failed. After performing the rollback and attempting again the following error appears

# openstack stack failures list --long <STACKNAME> 
{
  "status": "FAILED",
  "server_id": "11f3ab2c-3a97-4030-a47d-529e690cadac",
  "config_id": "28152387-0fc6-4177-b947-f9368a857fc3",
  "output_values": {
    "deploy_stdout": "",
    "deploy_stderr": "exception: connect failed\n\u001b[1;31mWarning: Scope(Class[Cinder::Api]): keystone_enabled is deprecated, use auth_strategy instead.\u001b[0m\n\u001b[1;31mWarning: Scope(Class[Glance::Api]): default_store not provided, it will be automatically set to glance.store.http.Store\u001b[0m\n\u001b[1;31mWarning: Scope(Class[Swift::Client]): Could not look up qualified variable '::swift::client_package_ensure'; class ::swift has not been evaluated\u001b[0m\n\u001b[1;31mWarning: Scope(Class[Heat]): keystone_user_domain_id is deprecated, use the name option instead.\u001b[0m\n\u001b[1;31mWarning: Scope(Class[Heat]): keystone_project_domain_id is deprecated, use the name option instead.\u001b[0m\n\u001b[1;31mError: '4' from left operand of 'in' expression is not a string at /etc/puppet/modules/neutron/manifests/plugins/ml2.pp:176 on node tivccosp01-controller-0.vcc.t-mobile.com\u001b[0m\n\u001b[1;31mError: '4' from left operand of 'in' expression is not a string at /etc/puppet/modules/neutron/manifests/plugins/ml2.pp:176 on node tivccosp01-controller-0.vcc.t-mobile.com\u001b[0m\n",
    "deploy_status_code": 1
  },