customer_id,first_name,last_name,email,phone,signup_date C001,John,Smith,john.smith@gmail.com,(555) 123-4567,2025-01-15 C002,John,Smith,JohnSmith@Gmail.com,555-123-4567,2025-02-03 C003,John,Smith,j.o.h.n.smith+shop@gmail.com,+15551234567,2025-02-19 C004,Jon,Smith,jon.smith@yahoo.com,(555) 987-6543,2025-01-22 C005,Maria,Garcia,maria@example.com,555.222.3333,2025-03-01 C006,Maria,Garcia,maria@example.com,5552223333,2025-03-10 C007,Maria,Garcia,maria@example.com,+1 (555) 222-3333,2025-03-15 C008,David,Lee,david.lee@work.com,(555) 444-1111,2025-02-01 C009,David,Lee,dlee@personal.com,555-444-1111,2025-02-28 C010,Sarah,Jones,sarah@example.com ,(555) 666-7777,2025-01-08 C011,Sarah,Jones,sarah@example.com,(555) 666-7777,2025-01-09 C012,Alice,Wong,alice.wong@example.com,(555) 333-9999,2025-03-22 C013,Robert,Brown,rob.brown@example.com,(555) 888-2222,2025-03-25 C014,Catherine,Doe,cdoe@example.com,(555) 111-0000,2025-01-30 C015,Katherine,Doe,cdoe@example.com,(555) 111-0000,2025-04-02