Kubernetes controller-manager and scheduler restarting multiple times

Question

# kubectl get pods -A
NAMESPACE      NAME                                 READY   STATUS    RESTARTS       AGE
default        nginx-deployment-6fd7c9fcc6-rcxpg    1/1     Running   0              107m
kube-flannel   kube-flannel-ds-4jrsz                1/1     Running   1              21h
kube-flannel   kube-flannel-ds-snbnc                1/1     Running   3 (112m ago)   21h
kube-system    coredns-5dd5756b68-krk7z             1/1     Running   1              19h
kube-system    coredns-5dd5756b68-qlfvw             1/1     Running   1              19h
kube-system    etcd-k8s-master                      1/1     Running   20             21h
kube-system    kube-apiserver-k8s-master            1/1     Running   5 (112m ago)   18h
kube-system    kube-controller-manager-k8s-master   1/1     Running   70 (15m ago)   19h
kube-system    kube-proxy-gjft2                     1/1     Running   1              21h
kube-system    kube-proxy-lswx4                     1/1     Running   1              21h
kube-system    kube-scheduler-k8s-master            1/1     Running   70 (16m ago)   21h
kube-system    metrics-server-98bc7f888-jh7m8       1/1     Running   0              52m

Failed to update lock: Put "https://<master-ip>:6443/apis/coordination.k8s.io/v1/namespaces/kube-system/leases/kube-scheduler?timeout=5s": net/http: request canceled (Client.Timeout exceeded while awaiting headers)
error retrieving resource lock kube-system/kube-scheduler: Get "https://<master-ip>:6443/apis/coordination.k8s.io/v1/namespaces/kube-system/leases/kube-scheduler?timeout=5s": context deadline exceeded
failed to renew lease kube-system/kube-scheduler: timed out waiting for the condition
Failed to release lock: Put "https://10.0.91.89:6443/apis/coordination.k8s.io/v1/namespaces/kube-system/leases/kube-scheduler?timeout=5s": net/http: request canceled (Client.Timeout exceeded while awaiting headers)
"Leaderelection lost"

kube-controller-manager-k8s-master and kube-scheduler-k8s-master both are restarting again and again every 30min once. When i check the logs from controller manager that gives error as mentioned above. When i launch my custom application pod it is also restarting again and again because of this. how to debug and fix this restarting issue of scheduler and controller-manager?

I disabled and stopped firewall. Checked if the certificates have valid expiration date and whether timezone in certificate matches the certificate. Even then the pods are restarting.