while editing items from frontend
it hangup for a while like picture number 1
imgur.com/BIN5FXR

and then it open the edit form this Missy way
and after pressing save and close it only save but doesn't close
...
and chrome console shows this errors:
Uncaught TypeError: window.addEvent is not a function
Failed to load resource: the server responded with a status of 404 (المجموعة غير موجودة)
Failed to load resource: the server responded with a status of 404 (المجموعة غير موجودة)
Synchronous XMLHttpRequest on the main thread is deprecated because of its detrimental effects to the end user's experience. For more help, check xhr.spec.whatwg.org/.
Failed to load resource: the server responded with a status of 404 (المجموعة غير موجودة)
Uncaught RangeError: Maximum call stack size exceeded.
Uncaught TypeError: $K2(...).accordion is not a function
Uncaught RangeError: Maximum call stack size exceeded.
Failed to load resource: the server responded with a status of 404 (المجموعة غير موجودة)
GET /templates/shaper_sportson/css/template_rtl.css

This seems like an outdated override issue.
Can you try browsing your site using a different template?

this is how the edit form popup shows:
imgur.com/iLX6wLP

can i PM my admin access to u and u check the problem for me plz ?

Can you remove the itemform.php override from your template's folder.
Make sure NOT to remove the core file.

cqn't find the file , where to search?? can i give you the access to my admin to help me plz?

This post will help you locate your overrides -> getk2.org/documentation/tutorials/174-templating-with-k2-and-the-concepts-of-sub-templates