The Due date field is not being populated using the REST API

[Charles Shaw]

I am trying to create a JIRA issue using the REST API.

On one of my software projects, the due date (and another date field) field is not populated by the data being sent. 

This is occuring if i delete a ticket and re-create via the REST API. The data i am sending is:

{
"fields": {
"project": {
"id": "11923"
},
"summary": "Confluence",
"issuetype": {
"id": "10101"
},
"customfield_10209": "2018-01-01",
"duedate": "2018-01-03",
"parent": {
"id": "24358"
},
"assignee": {
"name": "cshaw"
},
"reporter": {
"name": "cshaw"
},
"priority": {
"id": "1"
},
"timetracking": {
"originalEstimate": "4h",
"remainingEstimate": "4h"
},
"labels": [
"documentation"
],
"description": "Setup Confluence space and prepare for the project kick off meeting including project scope document."
}
}