Failed to update resource ibm_is_instance_group_manager_policy update

[SunithaGudisagarIBM1]

resource "ibm_is_vpc" "vpc2" {
	  name = "sunitha-vpc-tfp"
	}
	
	resource "ibm_is_subnet" "subnet2" {
	  name            = "sunitha-subnet-tfp"
	  vpc             = ibm_is_vpc.vpc2.id
	  zone            = "us-south-2"
	  ipv4_cidr_block = "10.240.64.0/28"
	}
	
	resource "ibm_is_ssh_key" "sshkey" {
	  name       = "sunitha-subnet-tfp"
	  public_key = "ssh-rsa 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 sunitha@Sunithas-MacBook-Pro.local"
	}
	
	resource "ibm_is_instance_template" "instancetemplate1" {
	   name    = "sunitha-instance-template"
	   image   = "r006-14140f94-fcc4-11e9-96e7-a72723715315"
	   profile = "bx2-8x32"
	
	   primary_network_interface {
		 subnet = ibm_is_subnet.subnet2.id
	   }
	
	   vpc       = ibm_is_vpc.vpc2.id
	   zone      = "us-south-2"
	   keys      = [ibm_is_ssh_key.sshkey.id]
	}
		
	resource "ibm_is_instance_group" "instance_group" {
		name =  "sunitha-instance-group"
		instance_template = ibm_is_instance_template.instancetemplate1.id
		instance_count =  1
		subnets = [ibm_is_subnet.subnet2.id]
	}

	resource "ibm_is_instance_group_manager" "instance_group_manager" {
		name = "sunitha-instance-group-manager"
		aggregation_window = 120
		instance_group = ibm_is_instance_group.instance_group.id
		cooldown = 300
		manager_type = "autoscale"
		enable_manager = true
		max_membership_count = 2
		min_membership_count = 1
	}
	
	resource "ibm_is_instance_group_manager_policy" "cpuPolicy" {
		instance_group = ibm_is_instance_group.instance_group.id
		instance_group_manager =  ibm_is_instance_group_manager.instance_group_manager.manager_id
		metric_type = "cpu"
		metric_value = 70
		policy_type = "target"
		name = "sunitha-instance-group-manager-policy-1"
	}