Help me in solving GSQ68B problem

My issue

failed on a Hidden test case

My code

/* Write a query to join the table 'Customer' and 'Purchase' using Customer_id as the common column in the table.
Output the joined table including the list of customers who hasn't made any purchases yet. */
SELECT 
    c.Customer_id, c.Customer_Name, c.Customer_Age, 
    p.Purchase_id, p.Customer_id, p.Purchase_amt, p.Last_purchase_month
FROM 
    Customer c
LEFT JOIN 
    Purchase p ON c.Customer_id = p.Customer_id
WHERE 
    p.Purchase_id IS NULL;

Learning course: Database management systems
Problem Link: Project - Left Join Two Tables in Database management systems