Persian Character error in PDF Report

In PDF report Persian Character shows (???) Question Marks, I have set the Unicode-UTF8 but didn’t change anything. How can I solve this problem?

My thoughts:
Check your database character settings.
Update your wkhtmltopdf.exe from the official site.
Apparently there are settings for wkhtmltopdf: https://wkhtmltopdf.org/libwkhtmltox/pagesettings.html#pagePdfGlobal maybe you can find the answer there.

My thoughts:
Check your database character settings.
Update your wkhtmltopdf.exe from the official site.
Apparently there are settings for wkhtmltopdf: https://wkhtmltopdf.org/libwkhtmltox/pagesettings.html#pagePdfGlobal maybe you can find the answer there.