Unable to override default Ansible variable from Satellite webui

Issue

• Overriding default Ansible variable doesn't work as expected for ntp role. After modifying variable, play fails with following error.

TASK [rhel-system-roles.timesync : Generate chrony.conf file] ******************
 201:
fatal: [host.example.com]: FAILED! => changed=false
 202:
  msg: 'AnsibleUndefinedVariable: ''unicode object'' has no attribute ''hostname'''

• string/array/json format of Ansible variable does not take affect while running Ansible role from Satellite webui.
• Unable to modify variable from Satellite webui