Customer phone number not updating

Question

Updating a customer phone number on Shopify through the API doesn't always change the number. I get no feedback from user errors either. I know that this number works as it was once set to this number, altered and I'm trying to alter it back. When setting this number in the addresses and altering, I get no issue.

The query:

mutation customerUpdate($input: CustomerInput!) {
  customerUpdate(input: $input) {
    userErrors {
      field
      message
    }
    customer {
     
      id
      firstName
      phone
     
    }
  }
} 

The GraphQL variables:

{
  "input": {
    "id":"gid://shopify/Customer/7792953622820",
    "firstName": "Sample",
    "addresses":[
        {
            "address1": "Road",
            "address2": "Suburb",
            "city": "City",
            "province":"Province",
            "country": "Country",
            "zip":"1234",
            "phone":"0118838945"
        }
    ]
  }
}