Repository save() is not committing or persisting data into table and returning an object with primary key which is already in table - oracle

Question

I am writing JPA implementation to replace JDBC implementation with query. I have used the Oracle database sequence object name in #SequenceGenerator as shown in the code. As a result, save() is returning an already existing data in the table instead of generating a new primary key and inserting into the table.
I think the sequence is generating existing primary key instead of generating a new one.
#Entity
#Table(name = "table")
public class TableDetail implements java.io.Serializable{
#Id
#GeneratedValue(strategy=GenerationType.SEQUENCE, generator = "table_seq")
#SequenceGenerator(sequenceName = "SEQ_TABLE", allocationSize = 1, name = "table_seq")
private Long AUDT_ID;
....
}
#Repository
public interface TableDetailDAO extends CrudRepository<TableDetail, Long> {
TableDetail save(TableDetail tableDetail);
}
#Service
#Transactional
public class TableDetailServiceImpl implements TableDetailService {
public void createAuditEvent(TableDetail tableDetail) {
#Autowired
TableDetailDAO tableDetailDAO;
TableDetail tableDetail =
tableDetailDAO.save(tableDetail);
}
}

Answer 1

So I figured out that it was due to my JDBC Database config file where I had defined this TransactionManager as shown. I had to remove this or define a JpaTransactionManager in this method. Right now, this definition was not letting JPA handle the commit due to which the data was not being persisted into the database.
This definition was present because it was actually a JDBC implementation before.
Also, I had to use GenerationType.AUTO because as far as my understanding, GenerationType.SEQUENCE is used only when there is no Sequence object defined in the Database.
/**
* Creates a handle to the TransactionManager.
*
* #return PlatformTransactionManager
*/
#Bean(name = "transactionManager")
public PlatformTransactionManager txManager() {
return new DataSourceTransactionManager(initializeDataSource());
}