Hindi character are not displaying in HTML Page even with UTF-8 encoding [duplicate]

I am author of openlibrary.site and i have added some books with hindi words but my browser display '?????' marks instead of those words, same page with same working method works fine on localhost(xampp) but not on my website. links of page https://openlibrary.site/booksinfo/kamayani-saundarya-e100752.php

or you may visit home page https://openlibrary.site but same problem there too.

I am using CloudFlare too (if there is any issue). Pages are get transferred after testing on localhost using ftp. pages info get generated with core-php with sql.