Automatic top-up

This is the code :

<form id=pay name=pay method="POST" action="">
 : <input type="Text" name="LMI_PAYMENT_AMOUNT" value = "10" class="window" size="7"> WMR<br><br>
    <input type="hidden" name="LMI_PAYMENT_DESC" value="   <?php print("$id_user $logus"); ?> ">
    <input type="hidden" name="LMI_PAYMENT_NO" value="<?php print (date("dmGis")); ?>">
    <input type="hidden" name="LMI_PAYEE_PURSE" value="R33333333333">
    <input type="hidden" name="LMI_SIM_MODE" value="0">
    <input type="Hidden" name="user" value="<?php print("$id_user"); ?>">
    <input type="Hidden" name="operation" value="open">
    <input type="submit" name="submit" value = "" class="field2" size="10">

It is necessary that not only pay, but also replenish the balance, that is, after a successful payment through the merchant, the user’s balance is replenished. How to implement?

Answer 1, authority 100%

You can’t do that with this code.
However, this can be done using the Click&Buy Merchant Interface, read the official wiki: Click&Buy Merchant Interface