Zephyr squad - Issue does not exist or you do not have permission to see it

Velladurai Muthupandi

I am trying to access different api calls on Zephyr squad cloud through Postman. Apart from "https://<our.domain>.attlassian.net>/rest/api/latest/serverInfo" for others I am not getting the desired response. 

For example "https://<our.domain>.attlassian.net>/rest/api/1.0/project/PROJ/versions" - I am getting 404 error. With the message as,   When I run the curl command, I get an HTTP 404 response with this data:

{"errorMessages":["

No project could be found with key 'PROJ'."],"errors":{}}

For "https://<our.domain>.attlassian.net>/rest/api/1.0/issue/PROJ-123?fields=id" I am getting 404 again with the message as 

{"errorMessages":["Issue does not exist or you do not have permission to see it."],"errors":{}}

I am using JWT token for authorization. 
Authorization Type: API Key 
Key: zapiAccessKey
Value: "ACCESS_KEY"
Authorization: "JWT_TOKEN"

NOTE: When I try the same api response in browser it works fine. Also, one of the api calls is working fine so I feel there is no issue with the authentication.

Am I missing something here? Any suggestion/solution would be great. Thanks in advance.