  Freudenthal duality (F-duality), an anti-involution of charge vectors keep
the entropy and attractor solutions invariant for an extremal supersymmetric
black hole. In this paper, we analyze the effect of F-duality on the entropy of
a near-extremal $STU$ black hole in $\mathcal{N}=2$ ungauged, four-dimensional
supergravity. We consider double-extremal black holes, whose attractor
solutions are fixed in terms of the black hole charges throughout the moduli
space. It is well known that JT gravity governs the dynamics of the
near-horizon regions of higher dimensional, near-extremal black holes. Owing to
this fact, we reduce the four-dimensional supergravity theory to two dimensions
to construct a Jackiw-Teitelboim (JT) gravity like model and compute the
near-extremal entropy. We then analyze the effect of F-duality on this entropy.
We show that the F-duality breaks down for the case of near-extremal solutions
if one considers the duality operation generated through near-extremal entropy
rather than the extremal one.
