Arabic alphabet mark issue on adobe illustrator typing

I have created a font in which alphabet marks are ok in notepad, word and etc. but in adobe illustrator, I got an issue with separated characters just after putting marks. the related image is attached.

How can I fix the problem?
Thanks
Untitled-1.jpg

Moved to correct forum.

If the font does not work correctly in Adobe Illustrator, I assume that some OpenType feature is not properly supported in Adobe Illustrator. Do other Arabic fonts work as expected?