Can not retrive timer from timerHandle stored in application db

We are persisting timerHandle object obtained while creating timers, in our application db so that we can use this handle later on to retrieve timer object and cancel the timer.

However, when I try to retrieve the timer from this timerHandle object (after retrieving it from our application db), I am getting following error.

(pool-11-thread-10) Unknown Exception: : javax.persistence.PersistenceException: org.hibernate.exception.GenericJDBCException: Cannot open connection
at org.hibernate.ejb.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1215) [:3.6.6.Final]
at org.hibernate.ejb.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1148) [:3.6.6.Final]
at org.hibernate.ejb.QueryImpl.getResultList(QueryImpl.java:255) [:3.6.6.Final]
at org.jboss.ejb3.timerservice.mk2.TimerServiceImpl.getPersistedTimer(TimerServiceImpl.java:951) [:1.0.0-alpha-13]
at org.jboss.ejb3.timerservice.mk2.TimerServiceImpl.getTimer(TimerServiceImpl.java:530) [:1.0.0-alpha-13]
at org.jboss.ejb3.timerservice.mk2.TimerHandleImpl.getTimer(TimerHandleImpl.java:107) [:1.0.0-alpha-13]
........................
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Caused by: org.jboss.util.NestedSQLException: Transaction is not active: tx=TransactionImple < ac, BasicAction: 0:ffff9493b5ec:126a:4ede0333:22a status: ActionStatus.ABORTED >; - nested throwable: (javax.resource.ResourceException: Transaction is not active: tx=TransactionImple < ac, BasicAction: 0:ffff9493b5ec:126a:4ede0333:22a status: ActionStatus.ABORTED >)
at org.jboss.resource.adapter.jdbc.WrapperDataSource.getConnection(WrapperDataSource.java:95) [:6.1.0.Final]
at org.hibernate.ejb.connection.InjectedDataSourceConnectionProvider.getConnection(InjectedDataSourceConnectionProvider.java:71) [:3.6.6.Final]
at org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:446) [:3.6.6.Final]
... 66 more
Caused by: javax.resource.ResourceException: Transaction is not active: tx=TransactionImple < ac, BasicAction: 0:ffff9493b5ec:126a:4ede0333:22a status: ActionStatus.ABORTED >
at org.jboss.resource.connectionmanager.TxConnectionManager.getManagedConnection(TxConnectionManager.java:403) [:6.1.0.Final]
at org.jboss.resource.connectionmanager.BaseConnectionManager2.allocateConnection(BaseConnectionManager2.java:496) [:6.1.0.Final]
at org.jboss.resource.connectionmanager.BaseConnectionManager2$ConnectionManagerProxy.allocateConnection(BaseConnectionManager2.java:941) [:6.1.0.Final]
at org.jboss.resource.adapter.jdbc.WrapperDataSource.getConnection(WrapperDataSource.java:89) [:6.1.0.Final]
... 68 more