How do I move next-gen issues to an Epic via Rest API?

Question

I get this error everytime I try to move an issue to an EPIC via a POST Rest API. I wasn't aware about the fact that it was a next-gen issue until I saw this error message. Now that I know, what should I do to eliminate this error? The error message is provided below: "errorMessages":["The request contains a next-gen issue. This operation can't add next-gen issues to epics. To add a next-gen issue to an epic, use the Edit issue operation and set the parent property (i.e., '\"parent\":{\"key\":\"PROJ-123\"}' where \"PROJ-123\" has an issue type at level one of the issue type hierarchy). See developer.atlassian.com for more details."],"errors":{}}

Trudy P Claspill · Answer

Hello @jiratickets

Were you able to resolve your issue with the answers I provided, or do you still have questions on this topic?

Trudy P Claspill · Answer

Refer to the documentation for the Edit Issue endpoint here:

https://developer.atlassian.com/cloud/jira/platform/rest/v2/api-group-issues/#api-rest-api-2-issue-issueidorkey-put

jiratickets · Answer

Hi Trudy,

Yes, I am a bit unclear on the Edit operation. I am using JIRA APIs to create jira issues with attachments. But, now that I need to link it to an existing EPIC, I get this issue. 
What do you mean by I need to use a different API endpoint? Could you please explain?

Thank you :)