Rediriger l'acheteur vers la page de paiement

<form method="POST" action="https://paiement.systempay.fr/vads-payment/">
<input type="hidden" name="vads_action_mode" value="INTERACTIVE" /> 
<input type="hidden" name="vads_amount" value="1315" /> 
<input type="hidden" name="vads_currency" value="978" />
<input type="hidden" name="vads_cust_id" value="1234" />
<input type="hidden" name="vads_cust_email" value="jg@sample.com" />
<input type="hidden" name="vads_ctx_mode" value="TEST" />
<input type="hidden" name="vads_order_id" value="CMD012859" />
<input type="hidden" name="vads_page_action" value="PAYMENT" />
<input type="hidden" name="vads_payment_cards" value="VISA;MASTERCARD" />
<input type="hidden" name="vads_payment_config" value="SINGLE" />
<input type="hidden" name="vads_site_id" value="12345678" /> 
<input type="hidden" name="vads_trans_date" value="20200326101407" /> 
<input type="hidden" name="vads_trans_id" value="362812" /> 
<input type="hidden" name="vads_version" value="V2" />
<input type="hidden" name="signature" value="NM25DPLKEbtGEHCDHn8MBT4ki6aJI/ODaWhCzCnAfvY="/>
<input type="submit" name="payer" value="Payer"/>
</form>