Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE Customers_cards (customer_id VARCHAR)
TABLE: CREATE TABLE Customers (customer_first_name VARCHAR, customer_id VARCHAR)
TABLE: CREATE TABLE Customers (customer_id VARCHAR, customer_first_name VARCHAR, card_type_code VARCHAR)

### Question ###
Show the customer ids and firstname without a credit card.

### Accurate SQL ###

SELECT customer_id, customer_first_name FROM Customers EXCEPT SELECT T1.customer_id, T2.customer_first_name FROM Customers_cards AS T1 JOIN Customers AS T2 ON T1.customer_id = T2.customer_id WHERE card_type_code = "Credit"