Where did you set the word ?i?ek? Is that a forum-title or a new post?
Did you check your database conversion? Some conversions could not save charakters like that. Please look into the database node-table if there is stored ?i?ek or cicek in the string
I have no problem with it at post or forum-titles
/forum/testforum-1/99-ı?ş??-?i?ek
/forum/ı?ş??-?i?ek