Database Error!

Error: Field 'last_seen' doesn't have a default value
Query: INSERT INTO users (uid, password, ip_address, first_seen) VALUES ("5d37b60cabd0c1.58914953", "c4361RKHs0K4qeCawlc6NwbhCdBO3KYR", "3.84.139.101", UNIX_TIMESTAMP())
File: /includes/database.class.php
Line: 98
Backtrace: