Hello,
the best way to progress on the subject, you have to go directly to the file (\YourWebSite\administrator\components\com_hikashop\views\user\tmpl\pay.php) and check that you have this around line 2 to 12 :
<form action="index.php?option=com_hikashop&ctrl=user" method="post" name="adminForm" id="adminForm">
<?php
echo JText::sprintf('PAY_X_TO_X', $this->currencyHelper->format($this->user->accumulated, $this->user->user_currency_id), @$this->user->name.' ('.$this->user->user_partner_email.')') .
'<br/>';
echo JText::sprintf('REDIRECTION_FOR_PAYMENT', $this->method) .
'<br/>';
echo JHTML::_('hikaselect.booleanlist', "pay", '', 0) .
'<br/>';
echo JText::_('AFFILIATE_PAYMENT_WARNING') .
'<br/>';
?>
And if not, and especially the red part, correct it to have the same code and see if that solve your issue.
Regards