JPA insert value but insert null
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Im trying to insert some values in Postgres with JPA using Hibernate. I have a mapped class with Annottions called Reserva and it has a field that is :

`@Column(nullable=false)
@Temporal(javax.persistence.TemporalType.DATE)
private Calendar dataFinal;`

I populate all  the fields of this class, no one is null, but when I call persist(reserva) it throws an error that dataFinal is null, but its not! I set all fields. Anyone knows whats is happening to me? Thanks in Advance!
Tip: When I persist another class that have this class(Reserva)  with(Cascade.Persist) it persists Reserva normally.