Jira Rest API throws 404 with issue does not exist

[Srihariharan Prabhakaran]

When we try to connect Jira Rest API, we are getting 404 with "issue does not exist or you do not have permission to see it" in excel VBA or in JAVA, but the same request and credentials works find in POSTMAN. 

VBA code:

.Open "GET", "<our domain>/rest/api/2/issue/DIGINF-6128/changelog", False

.setRequestHeader "Content-Type", "application/json"

.setRequestHeader "Accept", "application/json"
.setRequestHeader "Authorization", "Basic " & EncodeBase64(useremailid & ":" & JiraKey)

'.SetRequestHeader "Set-Cookie", sCookie '*** see Create a "Cookie"
.setRequestHeader "User-Agent", "Mozilla/5.0"

'MsgBox sCookie

.send

sRestAntwort = .responseText

MsgBox " status " & .Status

MsgBox sRestAntwort