From un- +‎ fix +‎ -ability.

unfixability (uncountable)

1. The state or condition of being unfixable.
   • 2002, Asma Barlas, "Believing women" in Islam: unreading patriarchal interpretations of the Qur'ān:

     For Muslims, the unfixability of meaning does not indicate an absence of truth, as it does for postmodernists.