Error 1002

I'm trying to insert a customer but when I send the XML is always giving the following error.

<Response status="0">
<Code>1002</Code>
<Message>ID Inválida foi passada</Message>
</Response>

I had already done this test before and was not giving this error, can anyone help?

Sample Code

<?php
$xml = '<?xml version="1.0" encoding="iso-8859-1"?>
<Customer>
    <Name>Sample Customer</Name>
    <PaymentsDue>0</PaymentsDue>
    <CurrencyCode>CNY</CurrencyCode>
    <BillingAddress>B-1104, 11F, Horizon International Tower, No. 6, ZhiChun Road, HaiDian District,</BillingAddress>
    <BillingCity>Beijing</BillingCity>
    <BillingZip>100088</BillingZip>
    <BillingCountry>China</BillingCountry>
    <BillingFax>+86-10-82637827</BillingFax>
    <ShippingAddress>4900 Hopyard Rd, Suit 310</ShippingAddress>
    <ShippingCity>Pleasanton</ShippingCity>
    <ShippingState>CA</ShippingState>
    <ShippingZip>94588</ShippingZip>
    <ShippingCountry>USA</ShippingCountry>
    <ShippingFax>+1-925-924-9600</ShippingFax>
    <Contacts>
        <Contact>
            <Salutation>Mr.</Salutation>
            <FirstName>John</FirstName>
            <LastName>Smith</LastName>
            <EMail>johnsmith@flaster.com</EMail>
            <Phone>+1-925-921-9201</Phone>
            <Mobile>+1-4054439562</Mobile>
        </Contact>
        <Contact>
            <Salutation>Ms.</Salutation>
            <FirstName>Shawla</FirstName>
            <LastName>Malkonni</LastName>
            <EMail>shawla@flaster.com</EMail>
            <Phone>+1-925-921-9111</Phone>
            <Mobile>+1-4054528653</Mobile>
        </Contact>
    </Contacts>
    <CustomFields>
        <CustomFieldLabel1>VAT ID</CustomFieldLabel1>
        <CustomFieldValue1>756399371</CustomFieldValue1>
        <CustomFieldLabel2>Reg.ID</CustomFieldLabel2>
        <CustomFieldValue2>673856</CustomFieldValue2>
        <CustomFieldLabel3>Website</CustomFieldLabel3>
        <CustomFieldValue3>www.zoho.com</CustomFieldValue3>
    </CustomFields>
    <Notes>Need to remind him of payments</Notes>
</Customer>';

?>

<form method='post' action='https://invoice.zoho.com/api/view/customers/create'>
<input type='text' name='apikey' value='codigonumber'>
<input type='text' name='ticket' value='ticketnumber'>
<input type='text' name='XMLString' value='<?=$xml?>'>
<input type='submit' name='submit' value='submit'>
</form>