To resolve this issue, use one of these options:
Remove the Data or Remote Collector node by running this command as root from any of the nodes in the cluster:

curl -ik -u 'admin:password' -X DELETE https://master_node_IP/casa/deployment/slice/node_to_remove_IP

Where:
password is the admin user password
master_node_IP is the IP of the Master node
node_to_remove_IP is the IP of the node that you want to remove from the cluster

Remove the Master or a Replica node by running this command as root from any of the nodes in the cluster:
Notes:
HA must be enabled for this call to succeed.
Large clusters might take additional time to repopulate the data.

curl -ik -u 'admin:password' -X DELETE https://master_node_IP/casa/deployment/slice/node_to_remove_IP/replacement_node_IP

Where:
password is the admin user password
master_node_IP is the IP of the Master node
node_to_remove_IP is the IP of the node that you want to remove from the cluster
replacement_node_IP is the IP of the node that replaces the Master or Replica node that you are removing