Transaction not connected, or was disconnected at NHibernate.Transaction.AdoTransaction.CheckNotZombied() at NHibernate.Transaction.AdoTransaction.Rollback()

Getting Transaction not connected, or was disconnected at NHibernate.Transaction.AdoTransaction.CheckNotZombied() at NHibernate.Transaction.AdoTransaction.Rollback() though Transaction is active and not committed/Rollbacked.