Automatic 5001 Decline for All Recurring Payments

[seekthepeace]

I am receiving an automatic 5001 decline for all recurring payments on https://seekingpeace.org/donate. Account ID: 37827

Every single response is identical:
stdClass Object
(
[AdditionalInfo] =>
[AuthorizationCode] =>
[EchoInput] =>
[FraudReview] =>
[GatewayTransactionNumber] =>
[ResultCode] => 5001
[ResultData] => Decline
[Server] => API-104 (this sometimes varies)
[TransactionNumber] =>
[VaultGUID] =>
[Version] => PaaS.20170619.003.051.004
)

Any idea what is going on? This only happens when I set it to recurring.

[CnP.Support.AM]

Good day @seekthepeace

Would you please share order number so that we know the reason for declined.

[seekthepeace]

Sorry thought I had closed this - had to change it to 999 installments as shwon below.
// Recurring
if ( $payment['subscription'] ) {
$recurring = $dom->createElement( 'Recurring', '' );
$recurring = $transaction->appendChild( $recurring );
$installment = $dom->createElement( 'Installment', 999 );
$installment = $recurring->appendChild( $installment );
/*$end_date = $dom->createElement( 'EndDate', '31/12/99' );
$end_date = $recurring->appendChild( $end_date );*/
$periodicity = $dom->createElement( 'Periodicity', 'Month' );
$periodicity = $recurring->appendChild( $periodicity );
$recurring_method = $dom->createElement( 'RecurringMethod', 'Installment' );
$recurring_method = $recurring->appendChild( $recurring_method );
}