Fatal error: Declaration of JToolbarButtonHikapopup

-- HikaShop version -- : 3.2.1
-- Joomla version -- : 3.8
-- PHP version -- : 7.2.11
-- Error-message(debug-mod must be tuned on) -- : Fatal error: Declaration of JToolbarButtonHikapopup

Hi
I've update my server php version to 7; and when I click for editing my products I see the blanks
When I turn on display error on my joomla; I encounter with this message:

Fatal error: Declaration of JToolbarButtonHikapopup::fetchButton($type = 'Modal', $name = '', $text = '', $url = '', $width = 640, $height = 480, $top = 0, $left = 0, $onClose = '', $title = '') must be compatible with Joomla\CMS\Toolbar\Button\PopupButton::fetchButton($type = 'Modal', $name = '', $text = '', $url = '', $width = 640, $height = 480, $top = 0, $left = 0, $onClose = '', $title = '', $footer = NULL) in /var/www/vhosts/--[my site]

---

.com/httpdocs/administrator/components/com_hikashop/buttons/hikapopup.php on line 45

is there any solution for this without reinstalling my hikashop? Because I have made a lot of change for my site, I dont want to lose its.