WAF Authentication Forms shows 404 after upgrade to SFOS 19.5.3 MR-3-Build652

Hi Sergejs Guridi Thank you for reaching out to the Sophos community. Yes you are correct In 19.5.3 MR-3 such an issue fix has been taken already (NC-119374 WAF Error 404 on Authentication page after upgrading the firmware from 19.5.1 to 19.5.2) However if the issue still remains there for you then I would suggest opening a support case to work on this (WAF Authentication Forms shows 404) further so that a support team member may drive it based on logs and observations and may validate the cause behind the error.It may be possible error is the same but the cause or reason is different..!

Also can you please confirm if your WAF is configured with the multiple domains?

If a support case has been logged already then please share the case details to review the case status and its progress.

WAF is configured for multiple domains, sure

Case number is 06945633

Thank you for sharing the case ID. I have added an internal note over the case to progress it further with the required logs.

This case is opened by our supplier. We don't have any response yet. Which logs exactly do you need?

Hi Sergejs Guridi I can see a Support access Id is shared already, Let the case owner review and collect the logs, and if he requires any further details he will connect with your supplier who has logged a case. 

Hi Sergejs Guridi I can see a Support access Id is shared already, Let the case owner review and collect the logs, and if he requires any further details he will connect with your supplier who has logged a case. 

Hi Sergejs Guridi Thank you for your cooperation & patience with us while the Support team has worked on this case with you and investigated it. As per the latest update of the case, I can see the reported issue has been investigated with the Dev team with ID NC-124519, and as of now workaround has been applied on your XG, and post that form-based authentication is working fine.