Problem with connection control with the Bank

I'm having some connection problems with the database. Here is my code and the exception.

Code

@Repository
public class MinhaClasseDAOImpl implements MinhaClasseDAO{

protected EntityManagerFactory entityManagerFactory = Persistence.createEntityManagerFactory("persistence_banco");

protected EntityManager entityManager;

protected EntityManager getEntityManager() {
    if(!entityManagerFactory.isOpen()){
        entityManagerFactory = Persistence.createEntityManagerFactory("persistence_banco");
    }
    return entityManagerFactory.createEntityManager();
}

public List<MinhaClasse> recuperarTotalMinhaClasse(int idTipoMinhaClasse, List<String> listaData){
    List<MinhaClasse> listaMinhaClasse = new ArrayList<MinhaClasse>();
    try{
        entityManager = getEntityManager();
        entityManager.getTransaction().begin();
        for(String data:listaData){
            String sql = "select sum(total), "
                    + "sum(quantidadeAguardou), sum(quantidadeNaoIdentificada), "
                    + "sum(quantidadeTeclouZero), sum(quantidadeTeclouZeroAguardou), "
                    + "sum(quantidadeTransferidaBC) "
                    + "from MinhaClasse where id_tipo_MinhaClasse = :idTipoMinhaClasse ";
                    if(data.length() == 10){
                        sql += "and data = :data";
                    }else{
                        sql += "and MONTH(data) = MONTH(:data) "
                                + "and YEAR(data) = YEAR(:data)";
                    }

            Query query = entityManager.createQuery(sql,Object[].class);
            query.setParameter("idTipoMinhaClasse", idTipoMinhaClasse);
            if(data.length() == 10){
                query.setParameter("data", DataUtil.converter(data));
            }else{
                query.setParameter("data", DataUtil.converter("01/"+data));
            }
            Object[] retorno = (Object[]) query.getSingleResult();
            MinhaClasse MinhaClasse = new MinhaClasse();
            if(retorno != null){
                MinhaClasse.setTotal(retorno[0]==null?0:Math.toIntExact((Long)retorno[0]));
                MinhaClasse.setQuantidadeAguardou(retorno[1]==null?0:Math.toIntExact((Long)retorno[1]));
                MinhaClasse.setQuantidadeNaoIdentificada(retorno[2]==null?0:Math.toIntExact((Long)retorno[2]));
                MinhaClasse.setQuantidadeTeclouZero(retorno[3]==null?0:Math.toIntExact((Long)retorno[3]));
                MinhaClasse.setQuantidadeTeclouZeroAguardou(retorno[4]==null?0:Math.toIntExact((Long)retorno[4]));
                MinhaClasse.setQuantidadeTransferidaBC(retorno[5]==null?0:Math.toIntExact((Long)retorno[5]));
                MinhaClasse.setPerfil(data);
            }
            listaMinhaClasse.add(MinhaClasse);
        }
    }catch(Exception ex){
        System.out.println("Erro ao recuperar MinhaClasse");
        ex.printStackTrace();
    }finally {
        fecharConexao();
    }
    return listaMinhaClasse;
}

private void fecharConexao(){
    if (entityManager.isOpen()){
        entityManager.close();
    }
}
}

Exception

Erro ao recuperar MinhaClassejava.lang.IllegalStateException: EntityManager is closed

at org.hibernate.jpa.internal.EntityManagerImpl.checkOpen(EntityManagerImpl.java:105)
at org.hibernate.jpa.spi.BaseQueryImpl.checkOpen(BaseQueryImpl.java:103)
at org.hibernate.jpa.spi.BaseQueryImpl.setParameter(BaseQueryImpl.java:617)
at org.hibernate.jpa.spi.AbstractQueryImpl.setParameter(AbstractQueryImpl.java:180)
at org.hibernate.jpa.spi.AbstractQueryImpl.setParameter(AbstractQueryImpl.java:49)
at com.everis.dao.impl.MinhaClasseDAOImpl.recuperarTotalMinhaClasse(MinhaClasseDAOImpl.java:58)
at com.everis.service.impl.MinhaClasseServiceImpl.listarHistoricoMinhaClasse(MinhaClasseServiceImpl.java:59)
at com.everis.ws.MinhaClasseWS.listarHistoricoMinhaClasse(MinhaClasseWS.java:35)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:221)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:136)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:110)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:817)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:731)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:959)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:893)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:968)
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:870)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:648)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:844)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:212)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:141)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:521)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1096)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:674)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1500)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1456)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)