When working on testing the k8s direct client, I was doing numerous restarts in vlab of the dataplane container. At one point, this led to a state where FRR did not have BGP configuration for the gateway peering between vpc-1and vpc-2 even though I had configured that peering from the start. Accordingly, ping between server-1 and server-2 no longer worked. A restart of dataplane did not resolve the issue, nor did a restart of FRR. However, a restart of FRR followed by a restart of dataplane resolved the issue and traffic began to pass.
I subsequently restarted dataplane numerous times to add status updates and never saw the issue again.