@nbhatti As has been said, we don't know. For what you are describing to happen there would need to be practically zero traffic passing, to both BGP peers, at the same time, for long enough to trigger the hold timer expiration. It doesn't sound like that is the case from what you have stated. Some occasional packet loss will not cause two TCP sessions to stop passing traffic at the same time and not recover.
I would packet capture the BGP sessions to the peers (TCP port 179) and try to capture the event. Then load it up into wireshark and see what happened to the session(s).
This would best be done at from place in the topography like a switch mirror port mirroring the traffic of the port connected to the tnsr node.