Invoking JIRA Rest API to create an issue containing a locked custom fields like Epic Name
<p>I'm trying to create an Epic Issue in JIRA using the REST API.</p>

<p>There is a field called "Epic Name", which is required and locked.
 When I submit the following JSON
URL: <a href="https://jira:443/jira/rest/api/latest/issue" rel="nofollow noreferrer">https://jira:443/jira/rest/api/latest/issue</a></p>

<pre><code>{"fields":{"project":{"key":"TEST"},"issuetype":{"name":"Epic"},"summary":"TestSummary","Epic Name":"TestName"}}
</code></pre>

<p>The Response is:</p>

<pre><code>Http Error : 400{"errorMessages":[],"errors":{"Epic Name":"Field 'Epic Name' cannot be set. It is not on the appropriate screen, or unknown."}}
</code></pre>

<p>What is wrong, since in the screen Epic Name is there and required (obviously, since it is a required attribute). What could be the problem?</p>

<p>Thanks</p>