debug ansible

I am trying to create a playbook that creates user in linux and I have declared my variables as a dictionary's type user_data but when I run it I have the following error :

FAILED! => {

"assertion": "ansible_failed_result.failed == false",
"changed": false,
"evaluated_to": false,
"msg": "Sorry, the unit test failed to create_user. Error = 'dict object' does not have a 'name' attribute."

thank you in advance for your future responses.