I could see that CDISC website is developed by ATLASSIAN
Are you referring to this: https://jira.cdisc.org ?
Atlassian writes Jira, and also provides hosted systems on it, but they do not administrate other people's Jira systems (beyond what is required for hosting Atlassian Cloud, or when there's a support case that needs admin to investigate/fix)
You will need to talk to the administrators of your system. There is a chance that some of them might be in the community here, but you can't expect them to find this question. We'd like to help, but we're not your admins, and it's the admins of your system you need to talk to in this case.
Hey @Sambasivarao Tedla ,
I'm familiar with CDISC as I know the Confluence administrator and a couple other folks that volunteer there. We (Atlassian) donate a Confluence Server license to CDISC. With our Server products, there isn't an option to delete your own account. An administrator will need to do this on your behalf.
The best path forward would be for you to use the CDISC contact form at https://www.cdisc.org/contact - make sure to include the email address associated with your CDISC Jira/Wiki account. I'd guess that they'll send you an email at that address to verify you own it in order to complete your account delete request.
Cheers,
Daniel | Atlassian Support