Error 409 When Adding External Testers in TestFlight

Hi Apple Team,

I am encountering an issue when trying to add a group of external testers in TestFlight. The process prompts me to fill out the testing information. However, upon submitting, the API /iris/v1/betaAppReviewDetails/:appId returns a 409 error, stating that the phone number must be a number.

Here is the request and response for your reference:

Request:

{
    "data": {
        "type": "betaAppReviewDetails",
        "id": "001000010",
        "attributes": {
            "contactFirstName": "Name",
            "contactLastName": "Surname",
            "contactPhone": "00900090001",
            "contactEmail": "me@email.com",
            "demoAccountRequired": false
        }
    }
}

Response:

{
  "errors" : [ {
    "id" : "4f29f252-2ae2-467d-856b-861d3940cb0b",
    "status" : "409",
    "code" : "ENTITY_ERROR.ATTRIBUTE.INVALID.INVALID_PHONE_NUMBER",
    "title" : "An attribute value has invalid phone number.",
    "detail" : "The format of the phone number is invalid",
    "source" : {
      "pointer" : "contactPhone"
    }
  } ]
}

Could you please assist in resolving this issue?

Thank you!

Best regards, Moisés B. Almeida