I am trying to integrate Jira server with Report Portal io. After logged in with admin credentials to Report Portal in administrative - plugins panel - I had uploaded "plugin-bts-jira-5.1.0-all.jar" to make plugin available.
Now I am trying to create Integration with correct BTS Username and BTS Password - but getting error as "an error occurred while connecting to server : impossible interact with integration. Connection refused".
Expected behavior
Integration should get created successfully.
Screenshots

Also for more reference adding company's jira server about screenshot - https://jira.[companyName].com
409 - network tab screenshot

I had tried - copying API Token from "https://id.atlassian.com/manage-profile/security/api-tokens", still getting same error.
Versions:
- OS - windows 10 Enterprise , Browser - Edge
- Version of RP - 5.6
Tried Solutions:
- Changing Jira URLs - like rest URL or URL till projects etc.
- Tried with API Token instead of password
- As I was getting 409 error - which generally occurs for version mismatch : I tried uploading different version of Jira bts jars.
- Tried with credentials of other person in my org- although I know this won't matter
- Changing Project Keys or Using Project Names.
All of these things resulted in same issue - "Impossible Interact" (Except for 3rd option - where for Jira cloud jars I got another error on upload itself).
Here is the GitHub bug that I had posted.
https://github.com/reportportal/reportportal/issues/1822
Report Portal io - Integration with Jira Server - error occurred while connecting to server : impossible interact with integration. Connection refused - Stack Overflow