Prayers have gone unanswered is in no sense the fault of the Lotus Sutra

I have found that even those who appear to believe just as the sutra teaches may not actually have strong faith at all, as you are already well aware. . . The fact that her prayers have gone unanswered is like a strong bow with a weak bowstring, or a fine sword in the hands of a coward. It is in no sense the fault of the Lotus Sutra. 12/4

The Writings of Nichiren Daishonin
The Royal Palace
Written to Shijo Kingo on April 12, 1275