Hello,
The problem caused by symbols of your language that you use in slug http://prntscr.com/nuxhu5
We sent your issue to our developers and I’ll inform you once they fix the problem.
But also I would not recommend you to use Arabic symbols for slugs not just because of this issue but because of SEO https://yoast.com/video/ask-yoast-slug-for-arabic-urls/
Regards