Hi @arup.sarkar,
Thanks for reaching out to the Auth0 Community!
I understand that you need help with configuring Passwordless Login for your Universal Login Page.
To modify the Universal Login Page, please navigate to your Auth0 Dashboard > Branding > Universal Login > Advanced Options > Login tab and enable the Customize Login Page switch.
Then click on the Templates drop-down menu and select the Lock (passwordless) option. Please do not forget to save your changes at the bottom of the page.
After that is complete, you should be able to use Passwordless Login.
Please let me know if you have any questions.
Thank you.