Getting Server failed to respond after submitting the self registration request.

[LakshiAthapaththu]

Describe the issue:
In self registration flow, after filling and submitting the self registration form, user is redirected to an error page saying Server failed to respond.

How to reproduce:

1. Enable self registration by following https://is.docs.wso2.com/en/6.0.0/guides/identity-lifecycles/self-registration-workflow/
2. Navigate to myaccount login portal.
3. Proceed with Create Account, fill and submit the form.
4. Observe redirection to an error page with Server failed to respond.

Screen.Recording.2023-06-20.at.17.04.08.mov

Expected behavior:
User should be able to self register successfully.

Environment information (Please complete the following information; remove any unnecessary fields) :

• Product Version: IS 6.2.0 Alpha 2
• OS: [e.g., Windows, Linux, Mac]
• Database: [e.g., MySQL, H2]
• Userstore: [e.g., LDAP, JDBC]

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