In Noto Nastaliq Urdu, the letter ݜ ("U+075C Arabic Letter Seen With Four Dots Above") doesn't form correctly. Its solitary shape remains no matter its position in the word. It is supposed to change shape, exactly like س ("U+0633 Arabic Letter Seen") but with four dots above, of course.
The attached image shows the text "ݜݨیاٗ شݨیاٗ سݨیاٗ"; the SEEN and SHEEN form correctly but the SEEN WITH FOUR DOTS retains its solitary form instead of correctly joining to the following letter.