Retrieve completed form with user inputs


We’re trying to get a user form with selected inputs using the form api:

POST /form/model
Provide variables needed to pre populated form fields and to render expression based form fields

    "formDefinitionId": "cf2773b4-ad3e-11ed-b305-7260a0ddc10d",
    "variables": {
        "MyFormText": "test"

It output the JSON form but no values are set (textbox in this extract)

                   "labelAlign": "top",
                    "value": "{{MyFormText}}",
                    "size": 12,

Does anyone know how this can be done ?

The end goal is to display the form with variables already existing