Question: Tell me the types of the policy used by the customer named "Dayana Robel".
SQL: SELECT DISTINCT t3.policy_type_code FROM customers AS t1 JOIN customers_policies AS t2 ON t1.customer_id  =  t2.customer_id JOIN available_policies AS t3 ON t2.policy_id  =  t3.policy_id WHERE t1.customer_name  =  "Dayana Robel"