DOC: fix json converter example and error message
diff --git a/src/sample.c b/src/sample.c
index 9e6baa8..645cb81 100644
--- a/src/sample.c
+++ b/src/sample.c
@@ -1643,7 +1643,7 @@
 	}
 
 	memprintf(err, "Unexpected input code type at file '%s', line %d. "
-	               "Allowed value are 'ascii', 'utf8', 'utf8p' and 'utf8pp'", file, line);
+	               "Allowed value are 'ascii', 'utf8', 'utf8s', 'utf8p' and 'utf8ps'", file, line);
 	return 0;
 }