After authentication user email otp is not getting to register email

I implemented Okta API.

  1. Enroll email otp confirmation mail is triggering
  2. when again user logging in email otp is not triggering.

the same is happening for sms authentication.

You might want to reach out to the Okta support team to see if the email is getting blocked.
https://support.okta.com/help/s/article/Activation-and-password-reset-emails-from-Okta-is-not-being-sent-to-a-specific-user

that link saying only about specific user. In my case all users