After some research what I found out was, it was one of the specific type Unicode Fonts PR is having difficulty interpreting. I tried with True Type fonts and the problem resolved!!! Info on Unicode font that d
This document presents information that will help font developers in creating OpenType fonts for Sinhala script as covered by the Unicode Standard 6.0. The Sinhala script is used to write the Sinhala language. It is also used to write Pali and Sanskrit....