VM flows are not getting completely flushed after VM deletion

VM related flows are not getting flushed completely after the VM deletion.
I have the following VM booted
stack@stack$ nova list
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ID Name Status Task State Power State Networks
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5dd5cdda-0002-49f5-805b-8e4c9d11df3c vm1 ACTIVE
Running net4=4.4.0.8
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stack@stack$ neutron port-list | grep 4.4.0.8
b74f865c-d394-43da-baba-71855c44a1ae fa:16:3e:1b:59:33 {"subnet_id": "49a5af66-697b-446f-8808-f5dd7a6d83de", "ip_address": "4.4.0.8"}
Here are the flows from OVSvAPP for this specific VM.
root@stack:~# ovs-ofctl dump-flows br-eth2 | grep fa:16:3e:1b:59:33
cookie=0xebde604343dc9c7e, duration=1220.397s, table=0, n_packets=2, n_bytes=748, idle_age=1216, priority=20,udp,in_port=2,dl_vlan=20,dl_dst=fa:16:3e:1b:59:33,nw_src=4.4.0.2,tp_src=67,tp_dst=68 actions=resubmit(,2),output:1
cookie=0xebde604343dc9c7e, duration=1220.397s, table=0, n_packets=1, n_bytes=376, idle_age=1216, priority=20,udp,in_port=2,dl_vlan=20,dl_dst=fa:16:3e:1b:59:33,nw_src=4.4.0.3,tp_src=67,tp_dst=68 actions=resubmit(,2),output:1
cookie=0xa37b181603cbb466, duration=360.389s, table=0, n_packets=0, n_bytes=0, idle_age=360, priority=20,icmp,in_port=2,dl_vlan=20,dl_dst=fa:16:3e:1b:59:33 actions=resubmit(,2),output:1
cookie=0xa37b181603cbb466, duration=360.388s, table=1, n_packets=0, n_bytes=0, idle_age=360, priority=10,ipv6,in_port=1,dl_vlan=20,dl_src=fa:16:3e:1b:59:33 actions=resubmit(,2),NORMAL
cookie=0x0, duration=360.388s, table=1, n_packets=0, n_bytes=0, idle_age=1220, priority=1,ipv6,in_port=1,dl_vlan=20,dl_src=fa:16:3e:1b:59:33 actions=resubmit(,5)
cookie=0xa37b181603cbb466, duration=360.389s, table=1, n_packets=0, n_bytes=0, idle_age=360, priority=10,ip,in_port=1,dl_vlan=20,dl_src=fa:16:3e:1b:59:33,nw_src=4.4.0.8 actions=resubmit(,2),NORMAL
cookie=0x0, duration=360.389s, table=1, n_packets=0, n_bytes=0, idle_age=1220, priority=1,ip,in_port=1,dl_vlan=20,dl_src=fa:16:3e:1b:59:33,nw_src=4.4.0.8 actions=resubmit(,5)
root@stack:~#
After VM deletion,
stack@stack$ nova delete vm1
Request to delete server vm1 has been accepted.
stack@stack$ nova list
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ID Name Status Task State Power State Networks
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stack@stack$
I still see few VM flows in ovsvapp
root@stack:~# ovs-ofctl dump-flows br-eth2 | grep fa:16:3e:1b:59:33
cookie=0x0, duration=945.709s, table=1, n_packets=0, n_bytes=0, idle_age=1805, priority=1,ipv6,in_port=1,dl_vlan=20,dl_src=fa:16:3e:1b:59:33 actions=resubmit(,5)
cookie=0x0, duration=945.710s, table=1, n_packets=0, n_bytes=0, idle_age=1805, priority=1,ip,in_port=1,dl_vlan=20,dl_src=fa:16:3e:1b:59:33,nw_src=4.4.0.8 actions=resubmit(,5)
root@stack:~#