Exception while releasing id from Id manager pool

There is a persistent exception occurring in Netvirt CSIT.

2017-05-17 04:18:13,784 | WARN | eChangeHandler-0 | CentralizedSwitchChangeListener | 332 - org.opendaylight.netvirt.vpnmanager-impl - 0.4.0.Carbon | No router data found for router id 08a7a314-c188-4499-bc04-5a1dcd47d769
2017-05-17 04:18:13,784 | ERROR | eChangeHandler-0 | ExternalRoutersListener | 341 - org.opendaylight.netvirt.natservice-impl - 0.4.0.Carbon | NAT Service : Unable to retrieve the primary NAPT switch for the router ID 100012 from RouterNaptSwitch model
2017-05-17 04:18:13,784 | INFO | eChangeHandler-0 | IdManager | 318 - org.opendaylight.genius.idmanager-impl - 0.2.0.Carbon | Releasing ID 08a7a314-c188-4499-bc04-5a1dcd47d769 from pool opendaylight-vni-ranges
2017-05-17 04:18:13,785 | INFO | eChangeHandler-0 | LockListener | 317 - org.opendaylight.genius.lockmanager-impl - 0.2.0.Carbon | Received add for lock opendaylight-vni-ranges08a7a314-c188-4499-bc04-5a1dcd47d769 : Lock{getLockName=opendaylight-vni-ranges08a7a314-c188-4499-bc04-5a1dcd47d769, getLockOwner=AsyncDataTreeChangeListenerBase-DataTreeChangeHandler-0, augmentations={}}
2017-05-17 04:18:13,785 | ERROR | eChangeHandler-0 | IdManager | 318 - org.opendaylight.genius.idmanager-impl - 0.2.0.Carbon | releaseId failed: ReleaseIdInput [_idKey=08a7a314-c188-4499-bc04-5a1dcd47d769, _poolName=opendaylight-vni-ranges, augmentation=[]]
org.opendaylight.genius.idmanager.IdManagerException: Id Entries does not exist
at org.opendaylight.genius.idmanager.IdManager.releaseIdFromLocalPool(IdManager.java:628)[318:org.opendaylight.genius.idmanager-impl:0.2.0.Carbon]
at org.opendaylight.genius.idmanager.IdManager.releaseId(IdManager.java:294)[318:org.opendaylight.genius.idmanager-impl:0.2.0.Carbon]
at org.opendaylight.yangtools.yang.binding.util.RpcMethodInvokerWithInput.invokeOn(RpcMethodInvokerWithInput.java:31)[47:org.opendaylight.mdsal.yang-binding:0.10.0.Carbon]
at org.opendaylight.yangtools.yang.binding.util.AbstractMappedRpcInvoker.invokeRpc(AbstractMappedRpcInvoker.java:52)[47:org.opendaylight.mdsal.yang-binding:0.10.0.Carbon]
at org.opendaylight.controller.md.sal.binding.impl.BindingDOMRpcImplementationAdapter.invoke(BindingDOMRpcImplementationAdapter.java:83)[146:org.opendaylight.controller.sal-binding-broker-impl:1.5.0.Carbon]
at org.opendaylight.controller.md.sal.binding.impl.BindingDOMRpcImplementationAdapter.invokeRpc(BindingDOMRpcImplementationAdapter.java:70)[146:org.opendaylight.controller.sal-binding-broker-impl:1.5.0.Carbon]
at org.opendaylight.controller.md.sal.dom.broker.impl.GlobalDOMRpcRoutingTableEntry.invokeRpc(GlobalDOMRpcRoutingTableEntry.java:39)[144:org.opendaylight.controller.sal-broker-impl:1.5.0.Carbon]
at org.opendaylight.controller.md.sal.dom.broker.impl.DOMRpcRoutingTable.invokeRpc(DOMRpcRoutingTable.java:177)[144:org.opendaylight.controller.sal-broker-impl:1.5.0.Carbon]
at org.opendaylight.controller.md.sal.dom.broker.impl.DOMRpcRouter.invokeRpc(DOMRpcRouter.java:102)[144:org.opendaylight.controller.sal-broker-impl:1.5.0.Carbon]
at Proxy5331e37e_0cfb_4d2f_b54e_94d43a4a5004.invokeRpc(Unknown Source)[:]
at Proxy2491353d_e182_4cef_b6fd_f34f61e0b4ad.invokeRpc(Unknown Source)[:]
at org.opendaylight.controller.md.sal.binding.impl.RpcServiceAdapter.invoke0(RpcServiceAdapter.java:65)[146:org.opendaylight.controller.sal-binding-broker-impl:1.5.0.Carbon]
at org.opendaylight.controller.md.sal.binding.impl.RpcServiceAdapter.access$000(RpcServiceAdapter.java:43)[146:org.opendaylight.controller.sal-binding-broker-impl:1.5.0.Carbon]
at org.opendaylight.controller.md.sal.binding.impl.RpcServiceAdapter$RpcInvocationStrategy.invoke(RpcServiceAdapter.java:159)[146:org.opendaylight.controller.sal-binding-broker-impl:1.5.0.Carbon]
at org.opendaylight.controller.md.sal.binding.impl.RpcServiceAdapter.invoke(RpcServiceAdapter.java:96)[146:org.opendaylight.controller.sal-binding-broker-impl:1.5.0.Carbon]
at com.sun.proxy.$Proxy127.releaseId(Unknown Source)[290:org.opendaylight.genius.idmanager-api:0.2.0.Carbon]
at org.opendaylight.netvirt.natservice.internal.NatOverVxlanUtil.releaseVNI(NatOverVxlanUtil.java:80)[341:org.opendaylight.netvirt.natservice-impl:0.4.0.Carbon]
at org.opendaylight.netvirt.natservice.internal.ExternalRoutersListener.remove(ExternalRoutersListener.java:1599)[341:org.opendaylight.netvirt.natservice-impl:0.4.0.Carbon]
at org.opendaylight.netvirt.natservice.internal.ExternalRoutersListener.remove(ExternalRoutersListener.java:135)[341:org.opendaylight.netvirt.natservice-impl:0.4.0.Carbon]
at org.opendaylight.genius.datastoreutils.AsyncDataTreeChangeListenerBase$DataTreeChangeHandler.run(AsyncDataTreeChangeListenerBase.java:149)[291:org.opendaylight.genius.mdsalutil-api:0.2.0.Carbon]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)[:1.8.0_121]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)[:1.8.0_121]
at java.lang.Thread.run(Thread.java:745)[:1.8.0_121]