1366 - Incorrect integer value: '' for column `agentur`.`whos_online`.`customer_id` at row 1

insert into whos_online (customer_id, full_name, session_id, ip_address, time_entry, time_last_click, last_page_url) values ('', 'Guest', '39853tkqu0vqo32u8arcf2neb3', '18.207.106.142', '1600708672', '1600708672', '/index.php?cat=c41_ICE-AGE-LIVE-.html&XTCsid=2d4qg7ftupcpr3opjmmv969b12')

[XT SQL Error]