JSFiddle - React, Tailwind, and code Playground
HTML
Do you already have a JIRA Ticket related to this correction:
<select name="ExistingJIRA">
<option value="YES">YES</option>
<option value="NO">NO</option>
</select>
<br></br>
Your JIRA Ticket ID: <input type="text" name="ticketID">
JavaScript
$("select[name=ExistingJIRA]").change(function() {
if (this.value == "YES")
$("input[name=ticketID]").prop("disabled", false);
else
$("input[name=ticketID]").prop("disabled", true);
}).change();