Find the phone numbers of customers using the most common policy type among the available policies.
SELECT customer_phone FROM available_policies WHERE policy_type_code  =  (SELECT policy_type_code FROM available_policies GROUP BY policy_type_code ORDER BY count(*) DESC LIMIT 1)
SELECT customer_phone FROM available_policies WHERE policy_type_code  =  (SELECT policy_type_code FROM available_policies GROUP BY policy_type_code ORDER BY count(*) DESC LIMIT 1)
[{'Customer_Phone': '242.763.9214'}, {'Customer_Phone': '1-416-503-7735x94204'}, {'Customer_Phone': '(777)537-7792'}, {'Customer_Phone': '813.178.8211x557'}, {'Customer_Phone': '405.090.8654x021'}]