That means, maybe there are certain languages which have first and second person reflexive, but they do not have the third person, but the other way around is absolutely impossible.
इसका मतलब है, शायद वहां कुछ भाषाएं हैं जिनमें first और second person reflexive है, लेकिन उनमें third person reflexive नहीं है, लेकिन दूसरी तरफ से बिल्कुल नामुमकिन है।