Jira has a built in date field called "Due Date" to be used when scheduling ssues to track and review, and inform teams about issue dates, comes with associated permission field "scheduling issue" and jira provides built jql to use with that field etc.
When configuring sla --> sla configuration --> new sla configuration --> sla value "Choose Negotiation Date Field" due date is not available as an option there but only custom date picker fields.
Due date should either be listed there in the drop down list or be available as an option to choose from as in
Type SLA duration as string
Use Due Date
Choose Negotiation Date Field