JIRA API to upload attachments

I am not using the JIRA plug-in but using the JIRA native REST API’s instead to create issues.
I have the following POST API:
http://${myJIRAURL}/rest/api/3/issue/40976/attachments

As per Atlassian documentation:
https://developer.atlassian.com/cloud/jira/platform/rest/v3/#api-rest-api-3-issue-issueIdOrKey-attachments-post

I have set the following on the header:
Content-Type = multipart/form-data
X-Atlassian-Token = no-check
Authorization …

Body:
selected “file” with Filepath set to the actual file: C:\Users…\Downloads\release_ST.zip

I get the response: 404 Not Found with blank body and the following header:
X-AREQUESTID: 28x250342x1
HTTP/1.1 404
X-ASEN: SEN-9877438
X-Content-Type-Options: nosniff
X-AUSERNAME: sysadmin
X-ASESSIONID: p3y86g
Set-Cookie: atlassian.xsrf.token=BXRB-XZFQ-WA82-U2D0|ed471e69745bb25b598ec1aae2f537c453be3e82|lin;path=/ JSESSIONID=519A82A21E3AB103AF75E3ECAA53475B;path=/;HttpOnly
Content-Length: 0
X-Seraph-LoginReason: OK
Date: Thu, 06 Jun 2019 14:28:16 GMT
Via: 1.1 browsermobproxy
Content-Type: text/html;charset=UTF-8

You should probably ask JIRA community about it. It’s not Katalon Studio related.

I just wanted to know the schema for the body.
Anyway, I found it just in case anyone is interested what values to enter inside Katalon:
https://community.atlassian.com/t5/Answers-Developer-Questions/JSON-format-for-Creating-JIRA-Issue-with-Attachment-using-REST/qaq-p/536575?lightbox-message-images-1009498=45872iB94B3C187D004094 (refer to the screenshots provided by [Danut M [StonikByte]] Feb 15, 2019