Database Error!

Error: Field 'last_seen' doesn't have a default value
Query: INSERT INTO users (uid, password, ip_address, first_seen) VALUES ("5d882641d7f826.47907098", "3sNRq2HqYtWXMuHCziCNkiAOLS5lST8N", "3.227.233.55", UNIX_TIMESTAMP())
File: /includes/database.class.php
Line: 98
Backtrace: