Self-Signed Certificate facing issue

Hi,
I am working on implementation of secure connection for Ignition on my laptop (localhost). I was following the below steps.
Secure Communication (SSL / TLS) - Ignition User Manual 8.1 - Ignition Documentation.

I added IP address and DNS and when I click on Install Self- Signed Certificate I get error as
image

Please let me know is any other configuration I missed or incorrectly entered.

Thanks

Now I am not able to login in to my Gateway.
image

Please guide me for resolving the issue.