Using customer managed keys will give administrators control over how data is encrypted to better meet compliance regulations, as well as allow for a more specific key rotation period. Using system-generated keys can sometimes lead to expired or exposed keys remaining in use, leading to insecure data. It is often recommended to use a customer managed key when the service is available.
At this time, the console UI does not have remediation steps available. For possible CLI remediation, see the product documentation (below) or use Terraform. Please also note that the encryption methodology cannot be changed for an existing resource, a new one will be created by using Terraform.
In Terraform -
References:
https://learn.microsoft.com/en-us/azure/healthcare-apis/
https://registry.terraform.io/providers/hashicorp/azurerm/latest/docs/resources/healthcare_service#cosmosdb_key_vault_key_versionless_id