Hi @pdztd (pdztd)​ , Thank you for reaching out to the Okta Community! 

I would like to preface my answer by saying that without any insight into your particular implementation, there is no way to provide an on-point answer to this.  

That being said, I would start by reviewing the app logs - assuming you checked the Okta side system logs, my expectation is that it says "sign in - successful" even though it failed for you. This is expected as Okta does not validate the authentication on the end point, the logs just confirm that the user account started the authentication process and the request was sent successfully to the Service Provider (SP). You will need to check the logs on the JIRA side to see if they offer any useful information. 

You could try capturing the assertion and review the that for any other useful information. You could try something like SAML Tracer or whatever tool you prefer.  

Then perhaps review the config steps to see if something is out of place.

There is an older post with some additional insight into what could go wrong. Although I'm not sure how much of it would apply to your use case, it's worth taking a look. 

If my answer helped, remember to mark it as best to increase its visibility for other members of the Okta Community who might have the same questions as you. 

Hope my answer helps! 

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