terraform import not working on resources with pkey

[pablo-ruth]

Hello,

We are trying to migrate from our Fortiadc provider (https://github.com/Ouest-France/terraform-provider-fortiadc) to this official provider, and we have a problem importing resources with "pkey".

For example with this Terraform config:

resource "fortiadc_load_balance_real_server" "rs1" {
  mkey        = "rs1"
  type        = "fqdn"
  fqdn        = "ourserver.mycorp.com"
  server_type = "static"
  status      = "enable"
}

resource "fortiadc_load_balance_pool" "rsp1" {
  mkey              = "rsp1"
  health_check      = "enable"
  health_check_list = "LB_HLTHCK_ICMP LB_HLTHCK_HTTPS"
}

resource "fortiadc_load_balance_pool_child_pool_member" "rsp1_rs1" {
  mkey           = "1"
  port           = "80"
  real_server_id = fortiadc_load_balance_real_server.rs1.id
  pkey           = fortiadc_load_balance_pool.rsp1.id
}

We tried to import the "fortiadc_load_balance_pool_child_pool_member" "rsp1_rs1" using multiple syntax, but we have errors:

$ terraform import fortiadc_load_balance_pool_child_pool_member.rsp1_rs1 1

fortiadc_load_balance_pool_child_pool_member.rsp1_rs1: Importing from ID "1"...
fortiadc_load_balance_pool_child_pool_member.rsp1_rs1: Import prepared!
  Prepared fortiadc_load_balance_pool_child_pool_member for import
fortiadc_load_balance_pool_child_pool_member.rsp1_rs1: Refreshing state... [id=1]
╷
│ Error: Error reading LoadBalancePoolChildPoolMember resource: 
│ {"payload":null}
│ 
│ 
╵

$ terraform import fortiadc_load_balance_pool_child_pool_member.rsp1_rs1 rsp1.1

fortiadc_load_balance_pool_child_pool_member.rsp1_rs1: Importing from ID "rsp1.1"...
fortiadc_load_balance_pool_child_pool_member.rsp1_rs1: Import prepared!
  Prepared fortiadc_load_balance_pool_child_pool_member for import
fortiadc_load_balance_pool_child_pool_member.rsp1_rs1: Refreshing state... [id=rsp1.1]
╷
│ Error: Error reading LoadBalancePoolChildPoolMember resource: 
│ {"payload":null}
│ 
│ 
╵

$ terraform import fortiadc_load_balance_pool_child_pool_member.rsp1_rs1 rsp1_1

fortiadc_load_balance_pool_child_pool_member.rsp1_rs1: Importing from ID "rsp1_1"...
fortiadc_load_balance_pool_child_pool_member.rsp1_rs1: Import prepared!
  Prepared fortiadc_load_balance_pool_child_pool_member for import
fortiadc_load_balance_pool_child_pool_member.rsp1_rs1: Refreshing state... [id=rsp1_1]
╷
│ Error: Error reading LoadBalancePoolChildPoolMember resource: 
│ {"payload":null}

Thanks