Hi,
Please edit the file "/http/components/com_hikamarket/views/vendormarket/tmpl/registration.php" and replace
<input type="text" id="<?php echo $this->form_type; ?>_paypal_email" name="data[<?php echo $this->form_type; ?>][vendor_params][paypal_email]" value="<?php echo $this->escape($this->element->vendor_params->paypal_email); ?>" class="inputbox <?php echo $r?'required':'';?> validate-email" maxlength="50"/><?php echo $r?' *':'';?>
By
<input type="text" id="<?php echo $this->form_type; ?>_paypal_email" name="data[<?php echo $this->form_type; ?>][vendor_params][paypal_email]" value="<?php echo $this->escape(@$this->element->vendor_params->paypal_email); ?>" class="inputbox <?php echo $r?'required':'';?> validate-email" maxlength="50"/><?php echo $r?' *':'';?>
It will fix the warning problem.
In order to not display the paypal line during the registration, you can change the option "ask for paypal" in the HikaMarket configuration (tab "Market", section "registration").
You can also remove the right "vendor / edit / paypal" so the vendor won't see the paypal email address afterwards.
Regards,