Order payments gateways in Restrict Content Pro. Add WordPress filter to for example the `functions.php` file of your WordPress theme.

pronamic-pay-rcp-payment-methods-order.php

<?php

function pronamic_pay_rcp_payment_methods_order( $gateways ) {
	/*
	 * Gateways in preferred order.
	 *
	 * @link https://github.com/wp-pay-extensions/restrict-content-pro/blob/3.0.0/src/Extension.php#L201-L242
	 */
	$order = array(
		'pronamic_pay_direct_debit_bancontact',
		'pronamic_pay_credit_card',
	);

	// Build gateways array in preferred order.
	$new_gateways = array();

	foreach ( $order as $gateway ) {
		// Check if payment method has been registered.
		if ( ! array_key_exists( $gateway, $gateways ) ) {
			continue;
		}

		$new_gateways[ $gateway ] = $gateways[ $gateway ];
	}

	// Merge gateways in order with all other gateways.
	$new_gateways = array_merge( $new_gateways, $gateways );

	// Return.
	return $new_gateways;
}

\add_filter( 'rcp_payment_gateways', 'pronamic_pay_rcp_payment_methods_order', 99 );