Audit log retention period is not set to at least 90 days for Azure PostgreSQL Server, this may make audit challenging.
In Azure Console -
In Terraform -
References:
https://learn.microsoft.com/en-us/azure/postgresql/flexible-server/quickstart-create-server-portal
https://registry.terraform.io/providers/hashicorp/azurerm/latest/docs/resources/postgresql_server#retention_days