Remove "Enter a valid email address or phone number" in user input box and Disable sign-up in a sign-up and sign-in user flow together

Question

Hi Team,

I am facing issue of Signin page with user flow.

1- When I am applying: https://graph.microsoft.com/beta/identity/authenticationEventsFlows/<user_flow_id>

{
    "@odata.type": "#microsoft.graph.externalUsersSelfServiceSignUpEventsFlow",
    "onInteractiveAuthFlowStart": {
        "@odata.type": "#microsoft.graph.onInteractiveAuthFlowStartExternalUsersSelfServiceSignUp",
        "isSignUpAllowed": true
    }
}

So signin page showing up -> Below user email id input box: No account? Create one

2- If I do

  "isSignUpAllowed": false

In user email input box its showing: **"**Enter a valid email address or phone number"

while entering "abc" and simple text in input box.
I don't want both option to be visible:

1- " **Enter a valid email address or phone number"
It should be Enter a valid email address" remove phone number. 2-** No account? Create one
Provide me solution around this. Is there any API or setting.