Skip enrollment SMS if user is already enrolled via Import APi

We have configured a MFA flow with custom SMS provider to send a sms.

The test user is already enrolled by the user import API with upsert option. Json below

[
    {
        "user_id": "auth0|google-oauth2|123456",
        "email": "tester@test.com",
        "mfa_factors": [
            {
                "phone": {
                    "value": "+6583838383"
                }
            },
            {
                "email": {
                    "value": "tester@test.com"
                }
            }
        ]
    }
]

Now when the user logs in for the first time. The SMS sent is from enrolment template even though the user is already enrolled. The subsequent login the sms verification template is used.

My question here is Why does the SMS received for the first time uses enrolment template even if user is already enrolled in MFA.

Thanks a lot